From f501d1f15912681d963c95977f7ff9dc4a87dda1 Mon Sep 17 00:00:00 2001 From: SproutSeeds <11943677+SproutSeeds@users.noreply.github.com> Date: Wed, 1 Apr 2026 06:51:27 +0000 Subject: [PATCH] chore(data): refresh Erdos catalog snapshots --- .../data/erdos_open_problems.md | 83 ++- .../data/erdos_problems.active.json | 526 +++++++--------- .../data/erdos_problems.all.json | 572 ++++++++++-------- .../data/erdos_problems.closed.json | 267 ++++++-- .../data/erdos_problems.open.json | 526 +++++++--------- 5 files changed, 1046 insertions(+), 928 deletions(-) diff --git a/packs/erdos-open-problems/data/erdos_open_problems.md b/packs/erdos-open-problems/data/erdos_open_problems.md index 46e175f..426f7b2 100644 --- a/packs/erdos-open-problems/data/erdos_open_problems.md +++ b/packs/erdos-open-problems/data/erdos_open_problems.md @@ -1,8 +1,8 @@ # Erdos Open Problems (Active Snapshot) -- generated_at_utc: `2026-03-05T15:52:31Z` +- generated_at_utc: `2026-04-01T06:51:20Z` - source_url: `https://erdosproblems.com/range/1-end` -- total_open: `691` +- total_open: `688` - [#1](https://erdosproblems.com/1) — OPEN | $500 | number theory, additive combinatorics — edited: 23 January 2026 — If $A\subseteq \{1,\ldots,N\}$ with $\lvert A\rvert=n$ is such that the subset sums $\sum_{a\in S}a$ are distinct for all $S\subseteq A$... - [#3](https://erdosproblems.com/3) — OPEN | $5000 | number theory, additive combinatorics, arithmetic progressions — edited: 23 January 2026 — If $A\subseteq \mathbb{N}$ has $\sum_{n\in A}\frac{1}{n}=\infty$ then must $A$ contain arbitrarily long arithmetic progressions? @@ -10,13 +10,13 @@ - [#7](https://erdosproblems.com/7) — VERIFIABLE | $25 | number theory, covering systems — edited: 22 January 2026 — Is there a distinct covering system all of whose moduli are odd? - [#9](https://erdosproblems.com/9) — OPEN | number theory, additive basis, primes — edited: 20 January 2026 — Let $A$ be the set of all odd integers $\geq 1$ not of the form $p+2^{k}+2^l$ (where $k,l\geq 0$ and $p$ is prime). Is the upper density... - [#10](https://erdosproblems.com/10) — OPEN | number theory, additive basis, primes — edited: 24 January 2026 — Is there some $k$ such that every large integer is the sum of a prime and at most $k$ powers of 2? -- [#11](https://erdosproblems.com/11) — FALSIFIABLE | number theory, additive basis — edited: 20 January 2026 — Is every large odd integer $n$ the sum of a squarefree number and a power of 2? +- [#11](https://erdosproblems.com/11) — OPEN | number theory, additive basis — edited: 20 January 2026 — Is every large odd integer $n$ the sum of a squarefree number and a power of 2? - [#12](https://erdosproblems.com/12) — OPEN | number theory — Let $A$ be an infinite set such that there are no distinct $a,b,c\in A$ such that $a\mid (b+c)$ and $b,c>a$. Is there such an $A$ with\[\... - [#14](https://erdosproblems.com/14) — OPEN | number theory, sidon sets, additive combinatorics — edited: 14 September 2025 — Let $A\subseteq \mathbb{N}$. Let $B\subseteq \mathbb{N}$ be the set of integers which are representable in exactly one way as the sum of... - [#15](https://erdosproblems.com/15) — OPEN | number theory, primes — Is it true that\[\sum_{n=1}^\infty(-1)^n\frac{n}{p_n}\]converges, where $p_n$ is the sequence of primes? - [#17](https://erdosproblems.com/17) — OPEN | number theory, primes — edited: 28 December 2025 — Are there infinitely many primes $p$ such that every even number $n\leq p-3$ can be written as a difference of primes $n=q_1-q_2$ where $... - [#18](https://erdosproblems.com/18) — OPEN | $250 | number theory, divisors, factorials — edited: 20 January 2026 — We call $m$ practical if every integer $1\leq n0$, there exist $M$ and $B\subset \{N+1,\l... - [#50](https://erdosproblems.com/50) — OPEN | $250 | number theory — Schoenberg proved that for every $c\in [0,1]$ the density of\[\{ n\in \mathbb{N} : \phi(n)0$\[\max( \lvert A+A\rvert,\lvert AA\rvert)\gg_\epsilon \lvert A... +- [#52](https://erdosproblems.com/52) — OPEN | $250 | number theory, additive combinatorics — edited: 23 March 2026 — Let $A$ be a finite set of integers. Is it true that for every $\epsilon>0$\[\max( \lvert A+A\rvert,\lvert AA\rvert)\gg_\epsilon \lvert A... - [#60](https://erdosproblems.com/60) — OPEN | graph theory, cycles — edited: 18 November 2025 — Does every graph on $n$ vertices with $>\mathrm{ex}(n;C_4)$ edges contain $\gg n^{1/2}$ many copies of $C_4$? - [#61](https://erdosproblems.com/61) — OPEN | graph theory — edited: 23 January 2026 — For any graph $H$ is there some $c=c(H)>0$ such that every graph $G$ on $n$ vertices that does not contain $H$ as an induced subgraph con... - [#62](https://erdosproblems.com/62) — OPEN | graph theory — edited: 23 January 2026 — If $G_1,G_2$ are two graphs with chromatic number $\aleph_1$ then must there exist a graph $G$ whose chromatic number is $4$ (or even $\a... @@ -50,7 +50,7 @@ - [#81](https://erdosproblems.com/81) — OPEN | graph theory — edited: 28 December 2025 — Let $G$ be a chordal graph on $n$ vertices - that is, $G$ has no induced cycles of length greater than $3$. Can the edges of $G$ be parti... - [#82](https://erdosproblems.com/82) — OPEN | graph theory — edited: 06 October 2025 — Let $F(n)$ be maximal such that every graph on $n$ vertices contains a regular induced subgraph on at least $F(n)$ vertices. Prove that $... - [#84](https://erdosproblems.com/84) — OPEN | graph theory, cycles — The cycle set of a graph $G$ on $n$ vertices is a set $A\subseteq \{3,\ldots,n\}$ such that there is a cycle in $G$ of length $\ell$ if a... -- [#85](https://erdosproblems.com/85) — FALSIFIABLE | graph theory, ramsey theory — edited: 06 December 2025 — Let $n\geq 4$ and $f(n)$ be minimal such that every graph on $n$ vertices with minimal degree $\geq f(n)$ contains a $C_4$. Is it true th... +- [#85](https://erdosproblems.com/85) — OPEN | graph theory, ramsey theory — edited: 06 December 2025 — Let $n\geq 4$ and $f(n)$ be minimal such that every graph on $n$ vertices with minimal degree $\geq f(n)$ contains a $C_4$. Is it true th... - [#86](https://erdosproblems.com/86) — OPEN | $100 | graph theory — edited: 27 December 2025 — Let $Q_n$ be the $n$-dimensional hypercube graph (so that $Q_n$ has $2^n$ vertices and $n2^{n-1}$ edges). Is it true that every subgraph... - [#87](https://erdosproblems.com/87) — OPEN | graph theory, ramsey theory — edited: 17 January 2026 — Let $\epsilon >0$. Is it true that, if $k$ is sufficiently large, then\[R(G)>(1-\epsilon)^kR(k)\]for every graph $G$ with chromatic numbe... - [#89](https://erdosproblems.com/89) — OPEN | $500 | geometry, distances — edited: 23 January 2026 — Does every set of $n$ distinct points in $\mathbb{R}^2$ determine $\gg n/\sqrt{\log n}$ many distinct distances? @@ -66,19 +66,18 @@ - [#102](https://erdosproblems.com/102) — OPEN | geometry — Let $c>0$ and $h_c(n)$ be such that for any $n$ points in $\mathbb{R}^2$ such that there are $\geq cn^2$ lines each containing more than... - [#103](https://erdosproblems.com/103) — OPEN | geometry, distances — Let $h(n)$ count the number of incongruent sets of $n$ points in $\mathbb{R}^2$ which minimise the diameter subject to the constraint tha... - [#104](https://erdosproblems.com/104) — OPEN | $100 | geometry — Given $n$ points in $\mathbb{R}^2$ the number of distinct unit circles containing at least three points is $o(n^2)$. -- [#106](https://erdosproblems.com/106) — FALSIFIABLE | geometry — Draw $n$ squares inside the unit square with no common interior point. Let $f(n)$ be the maximum possible sum of the side-lengths of the... +- [#106](https://erdosproblems.com/106) — FALSIFIABLE | geometry — edited: 06 March 2026 — Draw $n$ squares inside the unit square with no common interior point. Let $f(n)$ be the maximum possible sum of the side-lengths of the... - [#107](https://erdosproblems.com/107) — FALSIFIABLE | $500 | geometry, convex — edited: 23 January 2026 — Let $f(n)$ be minimal such that any $f(n)$ points in $\mathbb{R}^2$, no three on a line, contain $n$ points which form the vertices of a... - [#108](https://erdosproblems.com/108) — OPEN | graph theory, chromatic number, cycles — edited: 23 January 2026 — For every $r\geq 4$ and $k\geq 2$ is there some finite $f(k,r)$ such that every graph of chromatic number $\geq f(k,r)$ contains a subgra... - [#111](https://erdosproblems.com/111) — OPEN | graph theory, chromatic number, set theory — If $G$ is a graph let $h_G(n)$ be defined such that any subgraph of $G$ on $n$ vertices can be made bipartite after deleting at most $h_G... - [#112](https://erdosproblems.com/112) — OPEN | graph theory, ramsey theory — Let $k=k(n,m)$ be minimal such that any directed graph on $k$ vertices must contain either an independent set of size $n$ or a transitive... -- [#114](https://erdosproblems.com/114) — OPEN | $250 | polynomials, analysis — edited: 23 January 2026 — If $p(z)\in\mathbb{C}[z]$ is a monic polynomial of degree $n$ then is the length of the curve $\{ z\in \mathbb{C} : \lvert p(z)\rvert=1\}... +- [#114](https://erdosproblems.com/114) — FALSIFIABLE | $250 | polynomials, analysis — edited: 23 January 2026 — If $p(z)\in\mathbb{C}[z]$ is a monic polynomial of degree $n$ then is the length of the curve $\{ z\in \mathbb{C} : \lvert p(z)\rvert=1\}... - [#117](https://erdosproblems.com/117) — OPEN | group theory — edited: 23 January 2026 — Let $h(n)$ be minimal such that any group $G$ with the property that any subset of $>n$ elements contains some $x\neq y$ such that $xy=yx... - [#119](https://erdosproblems.com/119) — OPEN | $100 | analysis, polynomials — edited: 23 January 2026 — Let $z_i$ be an infinite sequence of complex numbers such that $\lvert z_i\rvert=1$ for all $i\geq 1$, and for $n\geq 1$ let\[p_n(z)=\pro... - [#120](https://erdosproblems.com/120) — OPEN | $100 | combinatorics — edited: 23 January 2026 — Let $A\subseteq\mathbb{R}$ be an infinite set. Must there be a set $E\subset \mathbb{R}$ of positive measure which does not contain any s... - [#122](https://erdosproblems.com/122) — OPEN | number theory — edited: 01 February 2026 — For which number theoretic functions $f$ is it true that, for any $F(n)$ such that $f(n)/F(n)\to 0$ for almost all $n$, there are infinit... - [#123](https://erdosproblems.com/123) — OPEN | $250 | number theory — edited: 20 January 2026 — Let $a,b,c\geq 1$ be three integers which are pairwise coprime. Is every large integer the sum of distinct integers of the form $a^kb^lc^... - [#124](https://erdosproblems.com/124) — OPEN | number theory, base representations, complete sequences — edited: 01 December 2025 — For any $d\geq 1$ and $k\geq 0$ let $P(d,k)$ be the set of integers which are the sum of distinct powers $d^i$ with $i\geq k$. Let $3\leq... -- [#125](https://erdosproblems.com/125) — OPEN | number theory, base representations — Let $A = \{ \sum\epsilon_k3^k : \epsilon_k\in \{0,1\}\}$ be the set of integers which have only the digits $0,1$ when written base $3$, a... - [#126](https://erdosproblems.com/126) — OPEN | $250 | number theory — Let $f(n)$ be maximal such that if $A\subseteq\mathbb{N}$ has $\lvert A\rvert=n$ then $\prod_{a\neq b\in A}(a+b)$ has at least $f(n)$ dis... - [#128](https://erdosproblems.com/128) — FALSIFIABLE | $250 | graph theory — edited: 31 October 2025 — Let $G$ be a graph with $n$ vertices such that every induced subgraph on $\geq \lfloor n/2\rfloor$ vertices has more than $n^2/50$ edges.... - [#129](https://erdosproblems.com/129) — OPEN | graph theory, ramsey theory — Let $R(n;k,r)$ be the smallest $N$ such that if the edges of $K_N$ are $r$-coloured then there is a set of $n$ vertices which does not co... @@ -100,13 +99,13 @@ - [#155](https://erdosproblems.com/155) — OPEN | additive combinatorics, sidon sets — Let $F(N)$ be the size of the largest Sidon subset of $\{1,\ldots,N\}$. Is it true that for every $k\geq 1$ we have\[F(N+k)\leq F(N)+1\]f... - [#156](https://erdosproblems.com/156) — OPEN | sidon sets — Does there exist a maximal Sidon set $A\subset \{1,\ldots,N\}$ of size $O(N^{1/3})$? - [#158](https://erdosproblems.com/158) — OPEN | sidon sets — Let $A\subset \mathbb{N}$ be an infinite set such that, for any $n$, there are most $2$ solutions to $a+b=n$ with $a\leq b$. Must\[\limin... -- [#159](https://erdosproblems.com/159) — OPEN | graph theory, ramsey theory — There exists some constant $c>0$ such that $$R(C_4,K_n) \ll n^{2-c}.$$ +- [#159](https://erdosproblems.com/159) — OPEN | $100 | graph theory, ramsey theory — edited: 07 March 2026 — There exists some constant $c>0$ such that $$R(C_4,K_n) \ll n^{2-c}.$$ - [#160](https://erdosproblems.com/160) — OPEN | additive combinatorics, arithmetic progressions — edited: 02 December 2025 — Let $h(N)$ be the smallest $k$ such that $\{1,\ldots,N\}$ can be coloured with $k$ colours so that every four-term arithmetic progression... - [#161](https://erdosproblems.com/161) — OPEN | $500 | combinatorics, hypergraphs, ramsey theory, discrepancy — edited: 16 January 2026 — Let $\alpha\in[0,1/2)$ and $n,t\geq 1$. Let $F^{(t)}(n,\alpha)$ be the smallest $m$ such that we can $2$-colour the edges of the complete... - [#162](https://erdosproblems.com/162) — OPEN | combinatorics, ramsey theory, discrepancy — edited: 30 December 2025 — Let $\alpha>0$ and $n\geq 1$. Let $F(n,\alpha)$ be the largest $k$ such that there exists some 2-colouring of the edges of $K_n$ in which... -- [#165](https://erdosproblems.com/165) — OPEN | $250 | graph theory, ramsey theory — edited: 28 December 2025 — Give an asymptotic formula for $R(3,k)$. +- [#165](https://erdosproblems.com/165) — OPEN | $250 | graph theory, ramsey theory — edited: 07 March 2026 — Give an asymptotic formula for $R(3,k)$. - [#167](https://erdosproblems.com/167) — FALSIFIABLE | graph theory — edited: 13 October 2025 — If $G$ is a graph with at most $k$ edge disjoint triangles then can $G$ be made triangle-free after removing at most $2k$ edges? -- [#168](https://erdosproblems.com/168) — OPEN | additive combinatorics — edited: 24 October 2025 — Let $F(N)$ be the size of the largest subset of $\{1,\ldots,N\}$ which does not contain any set of the form $\{n,2n,3n\}$. What is\[ \lim... +- [#168](https://erdosproblems.com/168) — OPEN | additive combinatorics — edited: 23 March 2026 — Let $F(N)$ be the size of the largest subset of $\{1,\ldots,N\}$ which does not contain any set of the form $\{n,2n,3n\}$. What is\[ \lim... - [#169](https://erdosproblems.com/169) — OPEN | additive combinatorics, arithmetic progressions — Let $k\geq 3$ and $f(k)$ be the supremum of $\sum_{n\in A}\frac{1}{n}$ as $A$ ranges over all sets of positive integers which do not cont... - [#170](https://erdosproblems.com/170) — OPEN | additive combinatorics — Let $F(N)$ be the smallest possible size of $A\subset \{0,1,\ldots,N\}$ such that $\{0,1,\ldots,N\}\subset A-A$. Find the value of\[\lim_... - [#172](https://erdosproblems.com/172) — OPEN | additive combinatorics, ramsey theory — edited: 01 February 2026 — Is it true that in any finite colouring of $\mathbb{N}$ there exist arbitrarily large finite $A$ such that all sums and products of disti... @@ -193,7 +192,7 @@ - [#326](https://erdosproblems.com/326) — OPEN | number theory, additive basis — Let $A\subset \mathbb{N}$ be an additive basis of order $2$. Must there exist $B=\{b_10$ and $n$ be some large integer. What is the size of the largest $A\subseteq \{1,\ldots,\lfloor cn\rfloor\}$ such that $n$ is not... - [#364](https://erdosproblems.com/364) — VERIFIABLE | number theory, powerful — edited: 20 December 2025 — Are there any triples of consecutive positive integers all of which are powerful (i.e. if $p\mid n$ then $p^2\mid n$)? - [#365](https://erdosproblems.com/365) — OPEN | number theory, powerful — edited: 31 October 2025 — Do all pairs of consecutive powerful numbers $n$ and $n+1$ come from solutions to Pell equations ? In other words, must either $n$ or $n+... -- [#366](https://erdosproblems.com/366) — VERIFIABLE | number theory, powerful — edited: 20 December 2025 — Are there any 2-full $n$ such that $n+1$ is 3-full? That is, if $p\mid n$ then $p^2\mid n$ and if $p\mid n+1$ then $p^3\mid n+1$. -- [#367](https://erdosproblems.com/367) — OPEN | number theory, powerful — edited: 08 February 2026 — Let $B_2(n)$ be the 2-full part of $n$ (that is, $B_2(n)=n/n'$ where $n'$ is the product of all primes that divide $n$ exactly once). Is... +- [#366](https://erdosproblems.com/366) — VERIFIABLE | number theory, powerful — edited: 23 March 2026 — Are there any $2$-full $n$ such that $n+1$ is $3$-full? That is, if $p\mid n$ then $p^2\mid n$ and if $p\mid n+1$ then $p^3\mid n+1$. +- [#367](https://erdosproblems.com/367) — OPEN | number theory, powerful — edited: 23 March 2026 — Let $B_2(n)$ be the $2$-full part of $n$ (that is, $B_2(n)=n/n'$ where $n'$ is the product of all primes that divide $n$ exactly once). I... - [#368](https://erdosproblems.com/368) — OPEN | number theory — How large is the largest prime factor of $n(n+1)$? -- [#369](https://erdosproblems.com/369) — OPEN | number theory — Let $\epsilon>0$ and $k\geq 2$. Is it true that, for all sufficiently large $n$, there is a sequence of $k$ consecutive integers in $\{1,... +- [#369](https://erdosproblems.com/369) — PROVED (LEAN) | number theory — Let $\epsilon>0$ and $k\geq 2$. Is it true that, for all sufficiently large $n$, there is a sequence of $k$ consecutive integers in $\{1,... - [#371](https://erdosproblems.com/371) — OPEN | number theory — edited: 23 January 2026 — Let $P(n)$ denote the largest prime factor of $n$. Show that the set of $n$ with $P(n)a_1\geq a_2\geq \cdots \geq a_k\geq 2$, has only finitely many solutions. - [#374](https://erdosproblems.com/374) — OPEN | number theory — For any $m\in \mathbb{N}$, let $F(m)$ be the minimal $k\geq 2$ (if it exists) such that there are $a_1<\cdots 0$ such that\[\sum_{p\leq n}1_{p\nmid \binom{2n}{n}}\frac{1}{p}\leq C\]for all $n$ (where the summatio... -- [#380](https://erdosproblems.com/380) — OPEN | number theory — We call an interval $[u,v]$ 'bad' if the greatest prime factor of $\prod_{u\leq m\leq v}m$ occurs with an exponent greater than $1$. Let... +- [#380](https://erdosproblems.com/380) — PROVED | number theory — We call an interval $[u,v]$ 'bad' if the greatest prime factor of $\prod_{u\leq m\leq v}m$ occurs with an exponent greater than $1$. Let... - [#382](https://erdosproblems.com/382) — OPEN | number theory — Let $u\leq v$ be such that the largest prime dividing $\prod_{u\leq m\leq v}m$ appears with exponent at least $2$. Is it true that $v-u=v... - [#383](https://erdosproblems.com/383) — OPEN | number theory — Is it true that for every $k$ there are infinitely many primes $p$ such that the largest prime divisor of\[\prod_{0\leq i\leq k}(p^2+i)\]... - [#385](https://erdosproblems.com/385) — OPEN | number theory — Let\[F(n) = \max_{\substack{mn... @@ -237,7 +236,7 @@ - [#393](https://erdosproblems.com/393) — OPEN | number theory, factorials — Let $f(n)$ denote the minimal $m\geq 1$ such that\[n! = a_1\cdots a_t\]with $a_1<\cdots 2$\[f(n) = f(n-f(n-1))+f(n-f(n-2)).\]Does $f(n)$ miss infinitely many integers? What is its behaviour? -- [#423](https://erdosproblems.com/423) — OPEN | number theory — edited: 16 January 2026 — Let $a_1=1$ and $a_2=2$ and for $k\geq 3$ choose $a_k$ to be the least integer $>a_{k-1}$ which is the sum of at least two consecutive te... -- [#424](https://erdosproblems.com/424) — OPEN | number theory — Let $a_1=2$ and $a_2=3$ and continue the sequence by appending to $a_1,\ldots,a_n$ all possible values of $a_ia_j-1$ with $i\neq j$. Is i... +- [#423](https://erdosproblems.com/423) — OPEN | number theory — edited: 23 March 2026 — Let $a_1=1$ and $a_2=2$ and for $k\geq 3$ choose $a_k$ to be the least integer $>a_{k-1}$ which is the sum of at least two consecutive te... +- [#424](https://erdosproblems.com/424) — OPEN | number theory — edited: 31 March 2026 — Let $a_1=2$ and $a_2=3$ and continue the sequence by appending to $a_1,\ldots,a_n$ all possible values of $a_ia_j-1$ with $i\neq j$. Is i... - [#425](https://erdosproblems.com/425) — OPEN | number theory, sidon sets — edited: 28 December 2025 — Let $F(n)$ be the maximum possible size of a subset $A\subseteq\{1,\ldots,N\}$ such that the products $ab$ are distinct for all $a0$ such that there are infinitely many $n$ where all primes $p\leq (2+\epsilon)\log n$ divide\[\prod_{1\leq i\leq... - [#458](https://erdosproblems.com/458) — FALSIFIABLE | number theory, primes — edited: 07 October 2025 — Let $[1,\ldots,n]$ denote the least common multiple of $\{1,\ldots,n\}$. Is it true that, for all $k\geq 1$,\[[1,\ldots,p_{k+1}-1]< p_k[1... - [#460](https://erdosproblems.com/460) — OPEN | number theory — edited: 14 January 2026 — Let $a_0=0$ and $a_1=1$, and in general define $a_k$ to be the least integer $>a_{k-1}$ for which $(n-a_k,n-a_i)=1$ for all $0\leq in\geq \max(A)$,\[\frac{\l... +- [#488](https://erdosproblems.com/488) — FALSIFIABLE | number theory — edited: 31 December 2025 — Let $A$ be a finite set and\[B=\{ n \geq 1 : a\mid n\textrm{ for some }a\in A\}.\]Is it true that, for every $m>n\geq \max(A)$,\[\frac{\l... - [#489](https://erdosproblems.com/489) — OPEN | number theory — Let $A\subseteq \mathbb{N}$ be a set such that $\lvert A\cap [1,x]\rvert=o(x^{1/2})$. Let\[B=\{ n\geq 1 : a\nmid n\textrm{ for all }a\in... - [#495](https://erdosproblems.com/495) — OPEN | diophantine approximation, number theory — Let $\alpha,\beta \in \mathbb{R}$. Is it true that\[\liminf_{n\to \infty} n \| n\alpha \| \| n\beta\| =0\]where $\|x\|$ is the distance f... - [#500](https://erdosproblems.com/500) — OPEN | $500 | graph theory, hypergraphs, turan number — edited: 05 October 2025 — What is $\mathrm{ex}_3(n,K_4^3)$? That is, the largest number of $3$-edges which can placed on $n$ vertices so that there exists no $K_4^... @@ -314,7 +312,7 @@ - [#539](https://erdosproblems.com/539) — OPEN | number theory — edited: 22 January 2026 — Let $h(n)$ be such that, for any set $A\subseteq \mathbb{N}$ of size $n$, the set\[\left\{ \frac{a}{(a,b)}: a,b\in A\right\}\]has size at... - [#544](https://erdosproblems.com/544) — OPEN | graph theory, ramsey theory — Show that\[R(3,k+1)-R(3,k)\to\infty\]as $k\to \infty$. Similarly, prove or disprove that\[R(3,k+1)-R(3,k)=o(k).\] - [#545](https://erdosproblems.com/545) — OPEN | graph theory, ramsey theory — edited: 02 December 2025 — Let $G$ be a graph with $m$ edges and no isolated vertices. Is the Ramsey number $R(G)$ maximised when $G$ is 'as complete as possible'?... -- [#548](https://erdosproblems.com/548) — FALSIFIABLE | graph theory — edited: 23 January 2026 — Let $n\geq k+1$. Every graph on $n$ vertices with at least $\frac{k-1}{2}n+1$ edges contains every tree on $k+1$ vertices. +- [#548](https://erdosproblems.com/548) — FALSIFIABLE | $100 | graph theory — edited: 07 March 2026 — Let $n\geq k+1$. Every graph on $n$ vertices with at least $\frac{k-1}{2}n+1$ edges contains every tree on $k+1$ vertices. - [#550](https://erdosproblems.com/550) — OPEN | graph theory, ramsey theory — Let $m_1\leq\cdots\leq m_k$ and $n$ be sufficiently large. If $T$ is a tree on $n$ vertices and $G$ is the complete multipartite graph wi... - [#552](https://erdosproblems.com/552) — OPEN | $100 | graph theory, ramsey theory — edited: 01 February 2026 — Determine the Ramsey number\[R(C_4,S_n),\]where $S_n=K_{1,n}$ is the star on $n+1$ vertices. In particular, is it true that, for any $c>0... - [#554](https://erdosproblems.com/554) — OPEN | graph theory, ramsey theory — edited: 08 February 2026 — Let $R_k(G)$ denote the minimal $m$ such that if the edges of $K_m$ are $k$-coloured then there is a monochromatic copy of $G$. Show that... @@ -330,10 +328,10 @@ - [#567](https://erdosproblems.com/567) — OPEN | graph theory, ramsey theory — edited: 18 January 2026 — Let $G$ be either $Q_3$ or $K_{3,3}$ or $H_5$ (the last formed by adding two vertex-disjoint chords to $C_5$). Is it true that, if $H$ ha... - [#568](https://erdosproblems.com/568) — OPEN | graph theory, ramsey theory — edited: 18 January 2026 — Let $G$ be a graph such that $R(G,T_n)\ll n$ for any tree $T_n$ on $n$ vertices and $R(G,K_n)\ll n^2$. Is it true that, for any $H$ with... - [#569](https://erdosproblems.com/569) — OPEN | graph theory, ramsey theory — edited: 18 January 2026 — Let $k\geq 1$. What is the best possible $c_k$ such that\[R(C_{2k+1},H)\leq c_k m\]for any graph $H$ on $m$ edges without isolated vertices? -- [#571](https://erdosproblems.com/571) — OPEN | graph theory, turan number — edited: 18 January 2026 — Show that for any rational $\alpha \in [1,2)$ there exists a bipartite graph $G$ such that\[\mathrm{ex}(n;G)\asymp n^{\alpha}.\] +- [#571](https://erdosproblems.com/571) — OPEN | graph theory, turan number — edited: 07 March 2026 — Show that for any rational $\alpha \in [1,2)$ there exists a bipartite graph $G$ such that\[\mathrm{ex}(n;G)\asymp n^{\alpha}.\] - [#572](https://erdosproblems.com/572) — OPEN | graph theory, turan number, cycles — edited: 18 January 2026 — Show that for $k\geq 3$\[\mathrm{ex}(n;C_{2k})\gg n^{1+\frac{1}{k}}.\] - [#573](https://erdosproblems.com/573) — OPEN | graph theory, turan number — edited: 18 January 2026 — Is it true that\[\mathrm{ex}(n;\{C_3,C_4\})\sim (n/2)^{3/2}?\] -- [#574](https://erdosproblems.com/574) — OPEN | graph theory, turan number — edited: 18 January 2026 — Is it true that, for $k\geq 2$,\[\mathrm{ex}(n;\{C_{2k-1},C_{2k}\})=(1+o(1))(n/2)^{1+\frac{1}{k}}.\] +- [#574](https://erdosproblems.com/574) — DISPROVED | graph theory, turan number — edited: 18 January 2026 — Is it true that, for $k\geq 2$,\[\mathrm{ex}(n;\{C_{2k-1},C_{2k}\})=(1+o(1))(n/2)^{1+\frac{1}{k}}.\] - [#575](https://erdosproblems.com/575) — OPEN | graph theory, turan number — edited: 18 January 2026 — If $\mathcal{F}$ is a finite set of finite graphs then $\mathrm{ex}(n;\mathcal{F})$ is the maximum number of edges a graph on $n$ vertice... - [#576](https://erdosproblems.com/576) — OPEN | graph theory, turan number — edited: 18 January 2026 — Let $Q_k$ be the $k$-dimensional hypercube graph (so that $Q_k$ has $2^k$ vertices and $k2^{k-1}$ edges). Determine the behaviour of\[\ma... - [#579](https://erdosproblems.com/579) — OPEN | graph theory, turan number — Let $\delta>0$. If $n$ is sufficiently large and $G$ is a graph on $n$ vertices with no $K_{2,2,2}$ and at least $\delta n^2$ edges then... @@ -353,7 +351,7 @@ - [#601](https://erdosproblems.com/601) — OPEN | $500 | graph theory, set theory — For which limit ordinals $\alpha$ is it true that if $G$ is a graph with vertex set $\alpha$ then $G$ must have either an infinite path o... - [#602](https://erdosproblems.com/602) — OPEN | combinatorics, set theory — Let $(A_i)$ be a family of sets with $\lvert A_i\rvert=\aleph_0$ for all $i$, such that for any $i\neq j$ we have $\lvert A_i\cap A_j\rve... - [#603](https://erdosproblems.com/603) — OPEN | combinatorics, set theory — edited: 28 December 2025 — Let $(A_i)$ be a family of countably infinite sets such that $\lvert A_i\cap A_j\rvert \neq 2$ for all $i\neq j$. Find the smallest cardi... -- [#604](https://erdosproblems.com/604) — OPEN | $500 | geometry, distances — edited: 15 October 2025 — Given $n$ distinct points $A\subset\mathbb{R}^2$ must there be a point $x\in A$ such that\[\#\{ d(x,y) : y \in A\} \gg n^{1-o(1)}?\]Or ev... +- [#604](https://erdosproblems.com/604) — OPEN | $500 | geometry, distances — edited: 23 March 2026 — Given $n$ distinct points $A\subset\mathbb{R}^2$ must there be a point $x\in A$ such that\[\#\{ d(x,y) : y \in A\} \gg n^{1-o(1)}?\]Or ev... - [#609](https://erdosproblems.com/609) — OPEN | graph theory, ramsey theory — Let $f(n)$ be the minimal $m$ such that if the edges of $K_{2^n+1}$ are coloured with $n$ colours then there must be a monochromatic odd... - [#610](https://erdosproblems.com/610) — OPEN | graph theory — edited: 02 December 2025 — For a graph $G$ let $\tau(G)$ denote the minimal number of vertices that include at least one from each maximal clique of $G$ (sometimes... - [#611](https://erdosproblems.com/611) — OPEN | graph theory — For a graph $G$ let $\tau(G)$ denote the minimal number of vertices that include at least one from each maximal clique of $G$ (sometimes... @@ -379,7 +377,6 @@ - [#643](https://erdosproblems.com/643) — OPEN | graph theory, hypergraphs — edited: 26 October 2025 — Let $f(n;t)$ be minimal such that if a $t$-uniform hypergraph on $n$ vertices contains at least $f(n;t)$ edges then there must be four ed... - [#644](https://erdosproblems.com/644) — OPEN | combinatorics — Let $f(k,r)$ be minimal such that if $A_1,A_2,\ldots$ is a family of sets, all of size $k$, such that for every collection of $r$ of the... - [#647](https://erdosproblems.com/647) — VERIFIABLE | $44 | number theory — edited: 05 October 2025 — Let $\tau(n)$ count the number of divisors of $n$. Is there some $n>24$ such that\[\max_{mk^2+1,\]where $p(m)$ denotes the least prime fac... - [#681](https://erdosproblems.com/681) — OPEN | number theory, primes — edited: 01 February 2026 — Is it true that for all large $n$ there exists $k$ such that $n+k$ is composite and\[p(n+k)>k^2,\]where $p(m)$ is the least prime factor... - [#683](https://erdosproblems.com/683) — OPEN | number theory, primes, binomial coefficients — edited: 31 December 2025 — Is it true that for every $1\leq k\leq n$ the largest prime divisor of $\binom{n}{k}$, say $P(\binom{n}{k})$, satisfies\[P\left(\binom{n}... -- [#684](https://erdosproblems.com/684) — OPEN | number theory, primes, binomial coefficients — edited: 23 January 2026 — For $0\leq k\leq n$ write\[\binom{n}{k} = uv\]where the only primes dividing $u$ are in $[2,k]$ and the only primes dividing $v$ are in $... +- [#684](https://erdosproblems.com/684) — OPEN | number theory, primes, binomial coefficients — edited: 01 April 2026 — For $0\leq k\leq n$ write\[\binom{n}{k} = uv\]where the only primes dividing $u$ are in $[2,k]$ and the only primes dividing $v$ are in $... - [#685](https://erdosproblems.com/685) — OPEN | number theory, primes, binomial coefficients — Let $\epsilon>0$ and $n$ be large depending on $\epsilon$. Is it true that for all $n^\epsilonr>2$, the value of\[\frac{\mathrm{ex}_r(n,K_k^r)}{\binom{n}{r}},\]where $\mathrm{ex}_r(n,K_k^r)$ is the largest num... -- [#713](https://erdosproblems.com/713) — OPEN | $500 | graph theory, turan number — edited: 06 October 2025 — Is it true that, for every bipartite graph $G$, there exists some $\alpha\in [1,2)$ and $c>0$ such that\[\mathrm{ex}(n;G)\sim cn^\alpha?\... +- [#713](https://erdosproblems.com/713) — OPEN | $500 | graph theory, turan number — edited: 07 March 2026 — Is it true that, for every bipartite graph $G$, there exists some $\alpha\in [1,2)$ and $c>0$ such that\[\mathrm{ex}(n;G)\sim cn^\alpha?\... - [#714](https://erdosproblems.com/714) — OPEN | graph theory, turan number — edited: 23 January 2026 — Is it true that\[\mathrm{ex}(n; K_{r,r}) \gg n^{2-1/r}?\] - [#719](https://erdosproblems.com/719) — OPEN | graph theory, hypergraphs — Let $\mathrm{ex}_r(n;K_{r+1}^r)$ be the maximum number of $r$-edges that can be placed on $n$ vertices without forming a $K_{r+1}^r$ (the... - [#723](https://erdosproblems.com/723) — FALSIFIABLE | combinatorics — If there is a finite projective plane of order $n$ then must $n$ be a prime power? A finite projective plane of order $n$ is a collection... @@ -439,7 +436,7 @@ - [#738](https://erdosproblems.com/738) — OPEN | graph theory, chromatic number — If $G$ has infinite chromatic number and is triangle-free (contains no $K_3$) then must $G$ contain every tree as an induced subgraph? - [#739](https://erdosproblems.com/739) — NOT PROVABLE | graph theory, chromatic number — edited: 01 October 2025 — Let $\mathfrak{m}$ be an infinite cardinal and $G$ be a graph with chromatic number $\mathfrak{m}$. Is it true that, for every infinite c... - [#740](https://erdosproblems.com/740) — OPEN | graph theory, chromatic number — Let $\mathfrak{m}$ be an infinite cardinal and $G$ be a graph with chromatic number $\mathfrak{m}$. Let $r\geq 1$. Must $G$ contain a sub... -- [#741](https://erdosproblems.com/741) — OPEN | additive combinatorics — Let $A\subseteq \mathbb{N}$ be such that $A+A$ has positive density. Can one always decompose $A=A_1\sqcup A_2$ such that $A_1+A_1$ and $... +- [#741](https://erdosproblems.com/741) — OPEN | additive combinatorics — edited: 01 April 2026 — Let $A\subseteq \mathbb{N}$ be such that $A+A$ has positive (upper) density. Can one always decompose $A=A_1\sqcup A_2$ such that $A_1+A_... - [#743](https://erdosproblems.com/743) — FALSIFIABLE | graph theory — Let $T_2,\ldots,T_n$ be a collection of trees such that $T_k$ has $k$ vertices. Can we always write $K_n$ as the edge disjoint union of t... - [#749](https://erdosproblems.com/749) — OPEN | additive combinatorics — Let $\epsilon>0$. Does there exist $A\subseteq \mathbb{N}$ such that the lower density of $A+A$ is at least $1-\epsilon$ and yet $1_A\ast... - [#750](https://erdosproblems.com/750) — OPEN | graph theory, chromatic number — edited: 14 October 2025 — Let $f(m)$ be some function such that $f(m)\to \infty$ as $m\to \infty$. Does there exist a graph $G$ of infinite chromatic number such t... @@ -496,7 +493,7 @@ - [#852](https://erdosproblems.com/852) — OPEN | number theory, primes — Let $d_n=p_{n+1}-p_n$, where $p_n$ is the $n$th prime. Let $h(x)$ be maximal such that for some $na$.... @@ -516,7 +513,6 @@ - [#879](https://erdosproblems.com/879) — OPEN | number theory — Call a set $S\subseteq \{1,\ldots,n\}$ admissible if $(a,b)=1$ for all $a\neq b\in S$. Let\[G(n) = \max_{S\subseteq \{1,\ldots,n\}} \sum_... - [#881](https://erdosproblems.com/881) — OPEN | number theory, additive basis — Let $A\subset\mathbb{N}$ be an additive basis of order $k$ which is minimal, in the sense that if $B\subset A$ is any infinite set then $... - [#883](https://erdosproblems.com/883) — OPEN | number theory, graph theory — edited: 24 October 2025 — For $A\subseteq \{1,\ldots,n\}$ let $G(A)$ be the graph with vertex set $A$, where two integers are joined by an edge if they are coprime... -- [#884](https://erdosproblems.com/884) — OPEN | number theory, divisors — Is it true that, for any $n$, if $d_1<\cdots 0$. Is it true that, for all large $n$, the number of divisors of $n$ in $(n^{1/2},n^{1/2}+n^{1/2-\epsilon})$ is $O_\epsilo... - [#887](https://erdosproblems.com/887) — OPEN | number theory, divisors — Is there an absolute constant $K$ such that, for every $C>0$, if $n$ is sufficiently large then $n$ has at most $K$ divisors in $(n^{1/2}... @@ -567,7 +563,7 @@ - [#961](https://erdosproblems.com/961) — OPEN | number theory — Let $f(k)$ be the minimal $n$ such that every set of $n$ consecutive integers $>k$ contains an integer divisible by a prime $>k$. Estimat... - [#962](https://erdosproblems.com/962) — OPEN | number theory — edited: 30 December 2025 — Let $k(n)$ be the maximal $k$ such that there exists $m\leq n$ such that each of the integers\[m+1,\ldots,m+k\]are divisible by at least... - [#963](https://erdosproblems.com/963) — OPEN | number theory — edited: 23 January 2026 — Let $f(n)$ be the maximal $k$ such that in any set $A\subset \mathbb{R}$ of size $n$ there is a subset $B\subseteq A$ of size $\lvert B\r... -- [#968](https://erdosproblems.com/968) — OPEN | number theory — Let $u_n=p_n/n$, where $p_n$ is the $n$th prime. Does the set of $n$ such that $u_n0$ such that, for all large $d$,\[p(a,d) > (1+c)... @@ -575,7 +571,7 @@ - [#973](https://erdosproblems.com/973) — OPEN | analysis — edited: 23 January 2026 — Does there exist a constant $C>1$ such that, for every $n\geq 2$, there exists a sequence $z_i\in \mathbb{C}$ with $z_1=1$ and $\lvert z_... - [#975](https://erdosproblems.com/975) — OPEN | number theory, divisors, polynomials — edited: 27 December 2025 — Let $f\in \mathbb{Z}[x]$ be an irreducible non-constant polynomial such that $f(n)\geq 1$ for all large $n\in\mathbb{N}$. Does there exis... - [#976](https://erdosproblems.com/976) — OPEN | number theory — edited: 01 February 2026 — Let $f\in \mathbb{Z}[x]$ be an irreducible polynomial of degree $d\geq 2$. Let $F_f(n)$ be maximal such that there exists $1\leq m\leq n$... -- [#978](https://erdosproblems.com/978) — OPEN | number theory — edited: 05 March 2026 — Let $f\in \mathbb{Z}[x]$ be an irreducible polynomial of degree $k>2$ (and suppose that $k\neq 2^l$ for any $l\geq 1$) such that the lead... +- [#978](https://erdosproblems.com/978) — OPEN | number theory — edited: 31 March 2026 — Let $f\in \mathbb{Z}[x]$ be an irreducible polynomial of degree $k>2$ (and suppose that $k\neq 2^l$ for any $l\geq 1$) such that the lead... - [#979](https://erdosproblems.com/979) — OPEN | number theory — edited: 19 September 2025 — Let $k\geq 2$, and let $f_k(n)$ count the number of solutions to\[n=p_1^k+\cdots+p_k^k,\]where the $p_i$ are prime numbers. Is it true th... - [#982](https://erdosproblems.com/982) — FALSIFIABLE | geometry, convex, distances — edited: 19 October 2025 — If $n$ distinct points in $\mathbb{R}^2$ form a convex polygon then some vertex has at least $\lfloor \frac{n}{2}\rfloor$ different dista... - [#983](https://erdosproblems.com/983) — OPEN | number theory — edited: 18 January 2026 — Let $n\geq 2$ and $\pi(n)0$, if $k$ is sufficiently large then, for all $n>0$ and interva... - [#1002](https://erdosproblems.com/1002) — OPEN | analysis, diophantine approximation — For any $0<\alpha<1$, let\[f(\alpha,n)=\frac{1}{\log n}\sum_{1\leq k\leq n}(\tfrac{1}{2}-\{ \alpha k\}).\]Does $f(\alpha,n)$ have an asym... - [#1003](https://erdosproblems.com/1003) — OPEN | number theory — edited: 31 October 2025 — Are there infinitely many solutions to $\phi(n)=\phi(n+1)$, where $\phi$ is the Euler totient function? - [#1004](https://erdosproblems.com/1004) — OPEN | number theory — Let $c>0$. If $x$ is sufficiently large then does there exist $n\leq x$ such that the values of $\phi(n+k)$ are all distinct for $1\leq k... @@ -598,7 +593,7 @@ - [#1017](https://erdosproblems.com/1017) — OPEN | graph theory — edited: 28 December 2025 — Let $f(n,k)$ be such that every graph on $n$ vertices and $k$ edges can be partitioned into at most $f(n,k)$ edge-disjoint complete graph... - [#1020](https://erdosproblems.com/1020) — FALSIFIABLE | graph theory, hypergraphs — edited: 28 December 2025 — Let $f(n;r,k)$ be the maximal number of edges in an $r$-uniform hypergraph which contains no set of $k$ many independent edges. For all $... - [#1029](https://erdosproblems.com/1029) — OPEN | $100 | graph theory, ramsey theory — If $R(k)$ is the Ramsey number for $K_k$, the minimal $n$ such that every $2$-colouring of the edges of $K_n$ contains a monochromatic co... -- [#1030](https://erdosproblems.com/1030) — OPEN | graph theory, ramsey theory — edited: 03 December 2025 — If $R(k,l)$ is the Ramsey number then prove the existence of some $c>0$ such that\[\lim_k \frac{R(k+1,k)}{R(k,k)}> 1+c.\] +- [#1030](https://erdosproblems.com/1030) — OPEN | graph theory, ramsey theory — edited: 23 March 2026 — Let $R(k,l)$ be the usual Ramsey number: the smallest $n$ such that if the edges of $K_n$ are coloured red and blue then there exists eit... - [#1032](https://erdosproblems.com/1032) — OPEN | graph theory, chromatic number — edited: 23 January 2026 — We say that a graph is $4$-chromatic critical if it has chromatic number $4$, and removing any edge decreases the chromatic number to $3$... - [#1033](https://erdosproblems.com/1033) — OPEN | graph theory — Let $h(n)$ be such that every graph on $n$ vertices with $>n^2/4$ many edges contains a triangle whose vertices have degrees summing to a... - [#1035](https://erdosproblems.com/1035) — OPEN | graph theory — Is there a constant $c>0$ such that every graph on $2^n$ vertices with minimum degree $>(1-c)2^n$ contains the $n$-dimensional hypercube... @@ -606,7 +601,7 @@ - [#1039](https://erdosproblems.com/1039) — OPEN | analysis, polynomials — edited: 27 December 2025 — Let $f(z)=\prod_{i=1}^n(z-z_i)\in \mathbb{C}[z]$ with $\lvert z_i\rvert \leq 1$ for all $i$. Let $\rho(f)$ be the radius of the largest d... - [#1040](https://erdosproblems.com/1040) — OPEN | analysis — edited: 01 February 2026 — Let $F\subseteq \mathbb{C}$ be a closed infinite set, and let $\mu(F)$ be the infimum of\[\lvert \{ z: \lvert f(z)\rvert < 1\}\rvert,\]as... - [#1041](https://erdosproblems.com/1041) — FALSIFIABLE | analysis, polynomials — edited: 06 December 2025 — Let $f(z)=\prod_{i=1}^n(z-z_i)\in \mathbb{C}[z]$ with $\lvert z_i\rvert < 1$ for all $i$. Must there always exist a path of length less t... -- [#1045](https://erdosproblems.com/1045) — FALSIFIABLE | analysis — edited: 30 December 2025 — Let $z_1,\ldots,z_n\in \mathbb{C}$ with $\lvert z_i-z_j\rvert\leq 2$ for all $i,j$, and\[\Delta(z_1,\ldots,z_n)=\prod_{i\neq j}\lvert z_i... +- [#1045](https://erdosproblems.com/1045) — OPEN | analysis — edited: 30 December 2025 — Let $z_1,\ldots,z_n\in \mathbb{C}$ with $\lvert z_i-z_j\rvert\leq 2$ for all $i,j$, and\[\Delta(z_1,\ldots,z_n)=\prod_{i\neq j}\lvert z_i... - [#1049](https://erdosproblems.com/1049) — OPEN | irrationality — edited: 28 September 2025 — Let $t>1$ be a rational number. Is\[\sum_{n=1}^\infty\frac{1}{t^n-1}=\sum_{n=1}^\infty \frac{\tau(n)}{t^n}\]irrational, where $\tau(n)$ c... - [#1052](https://erdosproblems.com/1052) — OPEN | $10 | number theory — edited: 28 September 2025 — A unitary divisor of $n$ is $d\mid n$ such that $(d,n/d)=1$. A number $n\geq 1$ is a unitary perfect number if it is the sum of its unita... - [#1053](https://erdosproblems.com/1053) — OPEN | number theory — Call a number $k$-perfect if $\sigma(n)=kn$, where $\sigma(n)$ is the sum of the divisors of $n$. Must $k=o(\log\log n)$? @@ -664,12 +659,11 @@ - [#1138](https://erdosproblems.com/1138) — OPEN | number theory, primes — edited: 23 January 2026 — Let $x/21$. If $d=\max_{p_n105$) such that $n-2^k$ is prime for all $1<2^k105$) such that $n-2^k$ is prime for all $1<2^kd_s(B)$ for every $B\subset \mathbb{N}$ with $00$ such that, for all large $n$ and all polynomials $P$ of degree $n$ with coefficients $\pm 1$,\[\max_{\l... - [#1151](https://erdosproblems.com/1151) — OPEN | analysis, polynomials — edited: 23 January 2026 — Given $a_1,\ldots,a_n\in [-1,1]$ let\[\mathcal{L}^nf(x) = \sum_{1\leq i\leq n}f(a_i)\ell_i(x)\]be the unique polynomial of degree $n-1$ w... - [#1152](https://erdosproblems.com/1152) — OPEN | analysis, polynomials — edited: 23 January 2026 — For $n\geq 1$ fix some sequence of $n$ distinct numbers $x_{1n},\ldots,x_{nn}\in [-1,1]$. Let $\epsilon=\epsilon(n)\to 0$. Does there alw... @@ -690,8 +684,11 @@ - [#1171](https://erdosproblems.com/1171) — OPEN | set theory, ramsey theory — edited: 26 January 2026 — Is it true that, for all finite $k<\omega$,\[\omega_1^2\to (\omega_1\omega, 3,\ldots,3)_{k+1}^2?\] - [#1172](https://erdosproblems.com/1172) — OPEN | set theory, ramsey theory — edited: 23 January 2026 — Establish whether the following are true assuming the generalised continuum hypothesis:\[\omega_3 \to (\omega_2,\omega_1+2)^2,\]\[\omega_... - [#1173](https://erdosproblems.com/1173) — OPEN | set theory, combinatorics — edited: 25 January 2026 — Assume the generalised continuum hypothesis. Let\[f: \omega_{\omega+1}\to [\omega_{\omega+1}]^{\leq \aleph_\omega}\]be a set mapping such... -- [#1174](https://erdosproblems.com/1174) — OPEN | set theory, ramsey theory — Does there exist a graph $G$ with no $K_4$ such that every edge colouring of $G$ with countably many colours contains a monochromatic $K_... +- [#1174](https://erdosproblems.com/1174) — NOT DISPROVABLE | set theory, ramsey theory — Does there exist a graph $G$ with no $K_4$ such that every edge colouring of $G$ with countably many colours contains a monochromatic $K_... - [#1175](https://erdosproblems.com/1175) — OPEN | set theory, chromatic number — Let $\kappa$ be an uncountable cardinal. Must there exist a cardinal $\lambda$ such that every graph with chromatic number $\lambda$ cont... -- [#1176](https://erdosproblems.com/1176) — OPEN | set theory, ramsey theory — edited: 24 January 2026 — Let $G$ be a graph with chromatic number $\aleph_1$. Is it true that there is a colouring of the edges with $\aleph_1$ many colours such... +- [#1176](https://erdosproblems.com/1176) — NOT DISPROVABLE | set theory, ramsey theory — edited: 24 January 2026 — Let $G$ be a graph with chromatic number $\aleph_1$. Is it true that there is a colouring of the edges with $\aleph_1$ many colours such... - [#1177](https://erdosproblems.com/1177) — OPEN | set theory, chromatic number, hypergraphs — edited: 23 January 2026 — Let $G$ be a finite $3$-uniform hypergraph, and let $F_G(\kappa)$ denote the collection of $3$-uniform hypergraphs with chromatic number... - [#1178](https://erdosproblems.com/1178) — OPEN | graph theory, hypergraphs — edited: 26 January 2026 — For $r\geq 3$ let $d_r(e)$ be the minimal $d$ such that\[\mathrm{ex}_r(n,\mathcal{F})=o(n^2),\]where $\mathcal{F}$ is the family of $r$-u... +- [#1181](https://erdosproblems.com/1181) — OPEN | number theory — edited: 07 March 2026 — Let $q(n,k)$ denote the least prime which does not divide $\prod_{1\leq i\leq k}(n+i)$. Is it true that there exists some $c>0$ such that... +- [#1182](https://erdosproblems.com/1182) — OPEN | graph theory, ramsey theory — Let $f(n)$ be maximal such that there is a connected graph $G$ with $n$ vertices and $f(n)$ edges such that\[R(K_3,G)= 2n-1.\]Let $F(n)$... +- [#1183](https://erdosproblems.com/1183) — OPEN | combinatorics, ramsey theory — Let $f(n)$ be maximal such that in any $2$-colouring of the subsets of $\{1,\ldots,n\}$ there is always a monochromatic family of at leas... diff --git a/packs/erdos-open-problems/data/erdos_problems.active.json b/packs/erdos-open-problems/data/erdos_problems.active.json index 647b433..24f0c1e 100644 --- a/packs/erdos-open-problems/data/erdos_problems.active.json +++ b/packs/erdos-open-problems/data/erdos_problems.active.json @@ -2,30 +2,32 @@ "schema_version": "1.0.0", "subset": "active", "active_status": "open", - "generated_at_utc": "2026-03-05T15:52:31Z", + "generated_at_utc": "2026-04-01T06:51:20Z", "source": { "site": "erdosproblems.com", "url": "https://erdosproblems.com/range/1-end", - "source_sha256": "72366d21b9530355396bef95b3ead90176a9c634b7ecd68fd30c85bad703a0c1", + "source_sha256": "870c67de08d4d2a7667ad4a3cd9b930d3a9809cca047a50fa20ab5b2b22fc23d", "solve_count": { - "raw": "488 solved out of 1179 shown", - "solved": 488, - "shown": 1179 + "raw": "495 solved out of 1183 shown", + "solved": 495, + "shown": 1183 } }, "summary": { - "total": 691, - "open": 691, + "total": 688, + "open": 688, "closed": 0, "unknown": 0, "status_label_counts": { "DECIDABLE": 2, + "DISPROVED": 1, "DISPROVED (LEAN)": 1, - "FALSIFIABLE": 29, - "NOT DISPROVABLE": 2, + "FALSIFIABLE": 27, + "NOT DISPROVABLE": 4, "NOT PROVABLE": 3, - "OPEN": 645, - "PROVED": 2, + "OPEN": 639, + "PROVED": 3, + "PROVED (LEAN)": 1, "VERIFIABLE": 7 } }, @@ -104,7 +106,6 @@ 122, 123, 124, - 125, 126, 128, 129, @@ -295,7 +296,6 @@ 454, 455, 456, - 457, 458, 460, 461, @@ -405,7 +405,6 @@ 643, 644, 647, - 650, 653, 654, 655, @@ -542,7 +541,6 @@ 879, 881, 883, - 884, 885, 886, 887, @@ -612,7 +610,6 @@ 993, 995, 996, - 997, 1002, 1003, 1004, @@ -695,7 +692,6 @@ 1144, 1145, 1146, - 1148, 1150, 1151, 1152, @@ -720,7 +716,10 @@ 1175, 1176, 1177, - 1178 + 1178, + 1181, + 1182, + 1183 ], "problems": [ { @@ -870,8 +869,8 @@ "problem_url": "/11", "status_bucket": "open", "status_dom_id": "open", - "status_label": "FALSIFIABLE", - "status_detail": "Open, but could be disproved with a finite counterexample.", + "status_label": "OPEN", + "status_detail": "This is open, and cannot be resolved with a finite computation.", "prize_amount": "", "statement": "Is every large odd integer $n$ the sum of a squarefree number and a power of 2?", "tags": [ @@ -993,8 +992,8 @@ ], "last_edited": "20 January 2026", "latex_path": "/latex/18", - "formalized": false, - "formalized_url": "", + "formalized": true, + "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/18.lean", "oeis_urls": [ "https://oeis.org/A005153" ], @@ -1013,7 +1012,7 @@ "tags": [ "combinatorics" ], - "last_edited": "25 January 2026", + "last_edited": "07 March 2026", "latex_path": "/latex/20", "formalized": true, "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/20.lean", @@ -1063,7 +1062,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/25.lean", "oeis_urls": [], "comments_problem_id": 25, - "comments_count": 2 + "comments_count": 7 }, { "problem_id": 28, @@ -1152,7 +1151,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/33.lean", "oeis_urls": [], "comments_problem_id": 33, - "comments_count": 4 + "comments_count": 5 }, { "problem_id": 36, @@ -1346,8 +1345,8 @@ ], "last_edited": "", "latex_path": "/latex/50", - "formalized": false, - "formalized_url": "", + "formalized": true, + "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/50.lean", "oeis_urls": [], "comments_problem_id": 50, "comments_count": 0 @@ -1388,7 +1387,7 @@ "number theory", "additive combinatorics" ], - "last_edited": "23 January 2026", + "last_edited": "23 March 2026", "latex_path": "/latex/52", "formalized": false, "formalized_url": "", @@ -1747,8 +1746,8 @@ "problem_url": "/85", "status_bucket": "open", "status_dom_id": "open", - "status_label": "FALSIFIABLE", - "status_detail": "Open, but could be disproved with a finite counterexample.", + "status_label": "OPEN", + "status_detail": "This is open, and cannot be resolved with a finite computation.", "prize_amount": "", "statement": "Let $n\\geq 4$ and $f(n)$ be minimal such that every graph on $n$ vertices with minimal degree $\\geq f(n)$ contains a $C_4$. Is it true that, for all large $n$, $f(n+1)\\geq f(n)$?", "tags": [ @@ -1878,7 +1877,7 @@ "https://oeis.org/A186704" ], "comments_problem_id": 91, - "comments_count": 5 + "comments_count": 6 }, { "problem_id": 92, @@ -2105,7 +2104,7 @@ "tags": [ "geometry" ], - "last_edited": "", + "last_edited": "06 March 2026", "latex_path": "/latex/106", "formalized": false, "formalized_url": "", @@ -2206,8 +2205,8 @@ "problem_url": "/114", "status_bucket": "open", "status_dom_id": "open", - "status_label": "OPEN", - "status_detail": "This is open, and cannot be resolved with a finite computation.", + "status_label": "FALSIFIABLE", + "status_detail": "Open, but could be disproved with a finite counterexample.", "prize_amount": "$250", "statement": "If $p(z)\\in\\mathbb{C}[z]$ is a monic polynomial of degree $n$ then is the length of the curve $\\{ z\\in \\mathbb{C} : \\lvert p(z)\\rvert=1\\}$ maximised when $p(z)=z^n-1$?", "tags": [ @@ -2220,7 +2219,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 114, - "comments_count": 3 + "comments_count": 4 }, { "problem_id": 117, @@ -2281,7 +2280,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/120.lean", "oeis_urls": [], "comments_problem_id": 120, - "comments_count": 1 + "comments_count": 3 }, { "problem_id": 122, @@ -2301,7 +2300,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 122, - "comments_count": 0 + "comments_count": 3 }, { "problem_id": 123, @@ -2345,29 +2344,6 @@ "comments_problem_id": 124, "comments_count": 13 }, - { - "problem_id": 125, - "problem_url": "/125", - "status_bucket": "open", - "status_dom_id": "open", - "status_label": "OPEN", - "status_detail": "This is open, and cannot be resolved with a finite computation.", - "prize_amount": "", - "statement": "Let $A = \\{ \\sum\\epsilon_k3^k : \\epsilon_k\\in \\{0,1\\}\\}$ be the set of integers which have only the digits $0,1$ when written base $3$, and $B=\\{ \\sum\\epsilon_k4^k : \\epsilon_k\\in \\{0,1\\}\\}$ be the set of integers which have only the digits $0,1$ when written base $4$. Does $A+B$ have positive density?", - "tags": [ - "number theory", - "base representations" - ], - "last_edited": "", - "latex_path": "/latex/125", - "formalized": true, - "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/125.lean", - "oeis_urls": [ - "https://oeis.org/A367090" - ], - "comments_problem_id": 125, - "comments_count": 13 - }, { "problem_id": 126, "problem_url": "/126", @@ -2826,13 +2802,13 @@ "status_dom_id": "open", "status_label": "OPEN", "status_detail": "This is open, and cannot be resolved with a finite computation.", - "prize_amount": "", + "prize_amount": "$100", "statement": "There exists some constant $c>0$ such that $$R(C_4,K_n) \\ll n^{2-c}.$$", "tags": [ "graph theory", "ramsey theory" ], - "last_edited": "", + "last_edited": "07 March 2026", "latex_path": "/latex/159", "formalized": false, "formalized_url": "", @@ -2919,7 +2895,7 @@ "graph theory", "ramsey theory" ], - "last_edited": "28 December 2025", + "last_edited": "07 March 2026", "latex_path": "/latex/165", "formalized": false, "formalized_url": "", @@ -2961,7 +2937,7 @@ "tags": [ "additive combinatorics" ], - "last_edited": "24 October 2025", + "last_edited": "23 March 2026", "latex_path": "/latex/168", "formalized": true, "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/168.lean", @@ -3102,7 +3078,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 176, - "comments_count": 1 + "comments_count": 3 }, { "problem_id": 177, @@ -3205,11 +3181,11 @@ ], "last_edited": "", "latex_path": "/latex/184", - "formalized": false, - "formalized_url": "", + "formalized": true, + "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/184.lean", "oeis_urls": [], "comments_problem_id": 184, - "comments_count": 0 + "comments_count": 1 }, { "problem_id": 187, @@ -3289,8 +3265,8 @@ ], "last_edited": "", "latex_path": "/latex/193", - "formalized": false, - "formalized_url": "", + "formalized": true, + "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/193.lean", "oeis_urls": [ "https://oeis.org/A231255" ], @@ -3693,7 +3669,7 @@ "https://oeis.org/A387704" ], "comments_problem_id": 241, - "comments_count": 2 + "comments_count": 3 }, { "problem_id": 242, @@ -3744,7 +3720,7 @@ "https://oeis.org/A000058" ], "comments_problem_id": 243, - "comments_count": 6 + "comments_count": 7 }, { "problem_id": 244, @@ -3872,8 +3848,8 @@ ], "last_edited": "07 December 2025", "latex_path": "/latex/254", - "formalized": false, - "formalized_url": "", + "formalized": true, + "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/254.lean", "oeis_urls": [], "comments_problem_id": 254, "comments_count": 3 @@ -3952,8 +3928,8 @@ ], "last_edited": "01 February 2026", "latex_path": "/latex/260", - "formalized": false, - "formalized_url": "", + "formalized": true, + "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/260.lean", "oeis_urls": [], "comments_problem_id": 260, "comments_count": 2 @@ -4162,7 +4138,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/274.lean", "oeis_urls": [], "comments_problem_id": 274, - "comments_count": 2 + "comments_count": 3 }, { "problem_id": 276, @@ -4270,7 +4246,7 @@ "https://oeis.org/A380791" ], "comments_problem_id": 283, - "comments_count": 2 + "comments_count": 3 }, { "problem_id": 287, @@ -4723,8 +4699,8 @@ ], "last_edited": "", "latex_path": "/latex/323", - "formalized": false, - "formalized_url": "", + "formalized": true, + "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/323.lean", "oeis_urls": [], "comments_problem_id": 323, "comments_count": 0 @@ -4769,7 +4745,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/325.lean", "oeis_urls": [], "comments_problem_id": 325, - "comments_count": 0 + "comments_count": 2 }, { "problem_id": 326, @@ -4790,7 +4766,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/326.lean", "oeis_urls": [], "comments_problem_id": 326, - "comments_count": 2 + "comments_count": 3 }, { "problem_id": 327, @@ -4849,7 +4825,7 @@ "number theory", "additive basis" ], - "last_edited": "08 December 2025", + "last_edited": "31 March 2026", "latex_path": "/latex/330", "formalized": true, "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/330.lean", @@ -4893,7 +4869,10 @@ "latex_path": "/latex/334", "formalized": false, "formalized_url": "", - "oeis_urls": [], + "oeis_urls": [ + "https://oeis.org/A045535", + "https://oeis.org/A062241" + ], "comments_problem_id": 334, "comments_count": 2 }, @@ -5019,13 +4998,13 @@ ], "last_edited": "30 September 2025", "latex_path": "/latex/342", - "formalized": false, - "formalized_url": "", + "formalized": true, + "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/342.lean", "oeis_urls": [ "https://oeis.org/A002858" ], "comments_problem_id": 342, - "comments_count": 11 + "comments_count": 18 }, { "problem_id": 345, @@ -5111,7 +5090,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/349.lean", "oeis_urls": [], "comments_problem_id": 349, - "comments_count": 8 + "comments_count": 12 }, { "problem_id": 351, @@ -5218,7 +5197,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/358.lean", "oeis_urls": [], "comments_problem_id": 358, - "comments_count": 19 + "comments_count": 21 }, { "problem_id": 359, @@ -5309,7 +5288,7 @@ "https://oeis.org/A175155" ], "comments_problem_id": 365, - "comments_count": 2 + "comments_count": 3 }, { "problem_id": 366, @@ -5319,12 +5298,12 @@ "status_label": "VERIFIABLE", "status_detail": "Open, but could be proved with a finite example.", "prize_amount": "", - "statement": "Are there any 2-full $n$ such that $n+1$ is 3-full? That is, if $p\\mid n$ then $p^2\\mid n$ and if $p\\mid n+1$ then $p^3\\mid n+1$.", + "statement": "Are there any $2$-full $n$ such that $n+1$ is $3$-full? That is, if $p\\mid n$ then $p^2\\mid n$ and if $p\\mid n+1$ then $p^3\\mid n+1$.", "tags": [ "number theory", "powerful" ], - "last_edited": "20 December 2025", + "last_edited": "23 March 2026", "latex_path": "/latex/366", "formalized": true, "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/366.lean", @@ -5342,12 +5321,12 @@ "status_label": "OPEN", "status_detail": "This is open, and cannot be resolved with a finite computation.", "prize_amount": "", - "statement": "Let $B_2(n)$ be the 2-full part of $n$ (that is, $B_2(n)=n/n'$ where $n'$ is the product of all primes that divide $n$ exactly once). Is it true that, for every fixed $k\\geq 1$,\\[\\prod_{n\\leq m0$ and $k\\geq 2$. Is it true that, for all sufficiently large $n$, there is a sequence of $k$ consecutive integers in $\\{1,\\ldots,n\\}$ all of which are $n^\\epsilon$-smooth?", "tags": [ @@ -5397,7 +5376,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 369, - "comments_count": 0 + "comments_count": 11 }, { "problem_id": 371, @@ -5467,7 +5446,7 @@ "https://oeis.org/A389148" ], "comments_problem_id": 374, - "comments_count": 0 + "comments_count": 1 }, { "problem_id": 375, @@ -5540,8 +5519,8 @@ "problem_url": "/380", "status_bucket": "open", "status_dom_id": "open", - "status_label": "OPEN", - "status_detail": "This is open, and cannot be resolved with a finite computation.", + "status_label": "PROVED", + "status_detail": "This has been solved in the affirmative.", "prize_amount": "", "statement": "We call an interval $[u,v]$ 'bad' if the greatest prime factor of $\\prod_{u\\leq m\\leq v}m$ occurs with an exponent greater than $1$. Let $B(x)$ count the number of $n\\leq x$ which are contained in at least one bad interval. Is it true that\\[B(x)\\sim \\#\\{ n\\leq x: P(n)^2\\mid n\\},\\]where $P(n)$ is the largest prime factor of $n$?", "tags": [ @@ -5558,7 +5537,7 @@ "https://oeis.org/A389100" ], "comments_problem_id": 380, - "comments_count": 5 + "comments_count": 9 }, { "problem_id": 382, @@ -5645,7 +5624,7 @@ "https://oeis.org/A280992" ], "comments_problem_id": 386, - "comments_count": 12 + "comments_count": 13 }, { "problem_id": 387, @@ -5686,7 +5665,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 388, - "comments_count": 5 + "comments_count": 10 }, { "problem_id": 389, @@ -5708,7 +5687,7 @@ "https://oeis.org/A375071" ], "comments_problem_id": 389, - "comments_count": 6 + "comments_count": 8 }, { "problem_id": 390, @@ -5799,7 +5778,7 @@ "https://oeis.org/A375077" ], "comments_problem_id": 396, - "comments_count": 1 + "comments_count": 30 }, { "problem_id": 398, @@ -5814,15 +5793,16 @@ "number theory", "factorials" ], - "last_edited": "", + "last_edited": "01 April 2026", "latex_path": "/latex/398", "formalized": true, "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/398.lean", "oeis_urls": [ + "https://oeis.org/A141399", "https://oeis.org/A146968" ], "comments_problem_id": 398, - "comments_count": 6 + "comments_count": 9 }, { "problem_id": 400, @@ -5839,8 +5819,8 @@ ], "last_edited": "", "latex_path": "/latex/400", - "formalized": false, - "formalized_url": "", + "formalized": true, + "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/400.lean", "oeis_urls": [], "comments_problem_id": 400, "comments_count": 0 @@ -6192,7 +6172,7 @@ "tags": [ "number theory" ], - "last_edited": "16 January 2026", + "last_edited": "23 March 2026", "latex_path": "/latex/423", "formalized": false, "formalized_url": "", @@ -6200,7 +6180,7 @@ "https://oeis.org/A005243" ], "comments_problem_id": 423, - "comments_count": 18 + "comments_count": 38 }, { "problem_id": 424, @@ -6214,7 +6194,7 @@ "tags": [ "number theory" ], - "last_edited": "", + "last_edited": "31 March 2026", "latex_path": "/latex/424", "formalized": true, "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/424.lean", @@ -6363,8 +6343,8 @@ ], "last_edited": "27 December 2025", "latex_path": "/latex/445", - "formalized": false, - "formalized_url": "", + "formalized": true, + "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/445.lean", "oeis_urls": [], "comments_problem_id": 445, "comments_count": 1 @@ -6496,28 +6476,6 @@ "comments_problem_id": 456, "comments_count": 2 }, - { - "problem_id": 457, - "problem_url": "/457", - "status_bucket": "open", - "status_dom_id": "open", - "status_label": "OPEN", - "status_detail": "This is open, and cannot be resolved with a finite computation.", - "prize_amount": "", - "statement": "Is there some $\\epsilon>0$ such that there are infinitely many $n$ where all primes $p\\leq (2+\\epsilon)\\log n$ divide\\[\\prod_{1\\leq i\\leq \\log n}(n+i)?\\]", - "tags": [ - "number theory" - ], - "last_edited": "07 October 2025", - "latex_path": "/latex/457", - "formalized": true, - "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/457.lean", - "oeis_urls": [ - "https://oeis.org/A391668" - ], - "comments_problem_id": 457, - "comments_count": 7 - }, { "problem_id": 458, "problem_url": "/458", @@ -6775,7 +6733,7 @@ "number theory", "additive combinatorics" ], - "last_edited": "", + "last_edited": "05 March 2026", "latex_path": "/latex/475", "formalized": false, "formalized_url": "", @@ -6904,8 +6862,8 @@ "problem_url": "/488", "status_bucket": "open", "status_dom_id": "open", - "status_label": "OPEN", - "status_detail": "This is open, and cannot be resolved with a finite computation.", + "status_label": "FALSIFIABLE", + "status_detail": "Open, but could be disproved with a finite counterexample.", "prize_amount": "", "statement": "Let $A$ be a finite set and\\[B=\\{ n \\geq 1 : a\\mid n\\textrm{ for some }a\\in A\\}.\\]Is it true that, for every $m>n\\geq \\max(A)$,\\[\\frac{\\lvert B\\cap [1,m]\\rvert }{m}< 2\\frac{\\lvert B\\cap [1,n]\\rvert}{n}?\\]", "tags": [ @@ -6917,7 +6875,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/488.lean", "oeis_urls": [], "comments_problem_id": 488, - "comments_count": 14 + "comments_count": 27 }, { "problem_id": 489, @@ -7168,7 +7126,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/517.lean", "oeis_urls": [], "comments_problem_id": 517, - "comments_count": 0 + "comments_count": 1 }, { "problem_id": 520, @@ -7478,12 +7436,12 @@ "status_dom_id": "open", "status_label": "FALSIFIABLE", "status_detail": "Open, but could be disproved with a finite counterexample.", - "prize_amount": "", + "prize_amount": "$100", "statement": "Let $n\\geq k+1$. Every graph on $n$ vertices with at least $\\frac{k-1}{2}n+1$ edges contains every tree on $k+1$ vertices.", "tags": [ "graph theory" ], - "last_edited": "23 January 2026", + "last_edited": "07 March 2026", "latex_path": "/latex/548", "formalized": false, "formalized_url": "", @@ -7809,7 +7767,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 569, - "comments_count": 0 + "comments_count": 2 }, { "problem_id": 571, @@ -7824,7 +7782,7 @@ "graph theory", "turan number" ], - "last_edited": "18 January 2026", + "last_edited": "07 March 2026", "latex_path": "/latex/571", "formalized": false, "formalized_url": "", @@ -7882,8 +7840,8 @@ "problem_url": "/574", "status_bucket": "open", "status_dom_id": "open", - "status_label": "OPEN", - "status_detail": "This is open, and cannot be resolved with a finite computation.", + "status_label": "DISPROVED", + "status_detail": "This has been solved in the negative.", "prize_amount": "", "statement": "Is it true that, for $k\\geq 2$,\\[\\mathrm{ex}(n;\\{C_{2k-1},C_{2k}\\})=(1+o(1))(n/2)^{1+\\frac{1}{k}}.\\]", "tags": [ @@ -7896,7 +7854,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 574, - "comments_count": 0 + "comments_count": 1 }, { "problem_id": 575, @@ -7999,7 +7957,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 583, - "comments_count": 1 + "comments_count": 3 }, { "problem_id": 584, @@ -8211,7 +8169,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/598.lean", "oeis_urls": [], "comments_problem_id": 598, - "comments_count": 0 + "comments_count": 2 }, { "problem_id": 600, @@ -8309,7 +8267,7 @@ "geometry", "distances" ], - "last_edited": "15 October 2025", + "last_edited": "23 March 2026", "latex_path": "/latex/604", "formalized": false, "formalized_url": "", @@ -8456,7 +8414,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/617.lean", "oeis_urls": [], "comments_problem_id": 617, - "comments_count": 0 + "comments_count": 1 }, { "problem_id": 619, @@ -8662,7 +8620,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 633, - "comments_count": 2 + "comments_count": 5 }, { "problem_id": 634, @@ -8831,26 +8789,6 @@ "comments_problem_id": 647, "comments_count": 6 }, - { - "problem_id": 650, - "problem_url": "/650", - "status_bucket": "open", - "status_dom_id": "open", - "status_label": "OPEN", - "status_detail": "This is open, and cannot be resolved with a finite computation.", - "prize_amount": "", - "statement": "Let $f(m)$ be such that if $A\\subseteq \\{1,\\ldots,N\\}$ has $\\lvert A\\rvert=m$ then every interval in $[1,\\infty)$ of length $2N$ contains $\\geq f(m)$ many distinct integers $b_1,\\ldots,b_r$ where each $b_i$ is divisible by some $a_i\\in A$, where $a_1,\\ldots,a_r$ are distinct. Estimate $f(m)$. In particular is it true that $f(m)\\ll m^{1/2}$?", - "tags": [ - "number theory" - ], - "last_edited": "", - "latex_path": "/latex/650", - "formalized": false, - "formalized_url": "", - "oeis_urls": [], - "comments_problem_id": 650, - "comments_count": 0 - }, { "problem_id": 653, "problem_url": "/653", @@ -9228,7 +9166,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/677.lean", "oeis_urls": [], "comments_problem_id": 677, - "comments_count": 0 + "comments_count": 7 }, { "problem_id": 679, @@ -9310,8 +9248,8 @@ ], "last_edited": "31 December 2025", "latex_path": "/latex/683", - "formalized": false, - "formalized_url": "", + "formalized": true, + "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/683.lean", "oeis_urls": [ "https://oeis.org/A006530", "https://oeis.org/A074399", @@ -9334,7 +9272,7 @@ "primes", "binomial coefficients" ], - "last_edited": "23 January 2026", + "last_edited": "01 April 2026", "latex_path": "/latex/684", "formalized": false, "formalized_url": "", @@ -9384,7 +9322,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/686.lean", "oeis_urls": [], "comments_problem_id": 686, - "comments_count": 16 + "comments_count": 37 }, { "problem_id": 687, @@ -9660,7 +9598,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 704, - "comments_count": 1 + "comments_count": 4 }, { "problem_id": 706, @@ -9715,13 +9653,13 @@ "tags": [ "number theory" ], - "last_edited": "", + "last_edited": "23 March 2026", "latex_path": "/latex/709", "formalized": false, "formalized_url": "", "oeis_urls": [], "comments_problem_id": 709, - "comments_count": 0 + "comments_count": 2 }, { "problem_id": 710, @@ -9800,7 +9738,7 @@ "graph theory", "turan number" ], - "last_edited": "06 October 2025", + "last_edited": "07 March 2026", "latex_path": "/latex/713", "formalized": false, "formalized_url": "", @@ -10118,17 +10056,17 @@ "status_label": "OPEN", "status_detail": "This is open, and cannot be resolved with a finite computation.", "prize_amount": "", - "statement": "Let $A\\subseteq \\mathbb{N}$ be such that $A+A$ has positive density. Can one always decompose $A=A_1\\sqcup A_2$ such that $A_1+A_1$ and $A_2+A_2$ both have positive density? Is there a basis $A$ of order $2$ such that if $A=A_1\\sqcup A_2$ then $A_1+A_1$ and $A_2+A_2$ cannot both have bounded gaps?", + "statement": "Let $A\\subseteq \\mathbb{N}$ be such that $A+A$ has positive (upper) density. Can one always decompose $A=A_1\\sqcup A_2$ such that $A_1+A_1$ and $A_2+A_2$ both have positive (upper) density? Is there a basis $A$ of order $2$ such that if $A=A_1\\sqcup A_2$ then $A_1+A_1$ and $A_2+A_2$ cannot both have bounded gaps?", "tags": [ "additive combinatorics" ], - "last_edited": "", + "last_edited": "01 April 2026", "latex_path": "/latex/741", "formalized": true, "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/741.lean", "oeis_urls": [], "comments_problem_id": 741, - "comments_count": 0 + "comments_count": 3 }, { "problem_id": 743, @@ -10711,7 +10649,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 809, - "comments_count": 0 + "comments_count": 1 }, { "problem_id": 810, @@ -10770,8 +10708,8 @@ ], "last_edited": "", "latex_path": "/latex/812", - "formalized": false, - "formalized_url": "", + "formalized": true, + "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/812.lean", "oeis_urls": [], "comments_problem_id": 812, "comments_count": 0 @@ -11041,7 +10979,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/835.lean", "oeis_urls": [], "comments_problem_id": 835, - "comments_count": 4 + "comments_count": 5 }, { "problem_id": 836, @@ -11287,7 +11225,7 @@ "https://oeis.org/A390769" ], "comments_problem_id": 853, - "comments_count": 2 + "comments_count": 3 }, { "problem_id": 854, @@ -11317,8 +11255,8 @@ "problem_url": "/855", "status_bucket": "open", "status_dom_id": "open", - "status_label": "FALSIFIABLE", - "status_detail": "Open, but could be disproved with a finite counterexample.", + "status_label": "OPEN", + "status_detail": "This is open, and cannot be resolved with a finite computation.", "prize_amount": "", "statement": "If $\\pi(x)$ counts the number of primes in $[1,x]$ then is it true that (for large $x$ and $y$)\\[\\pi(x+y) \\leq \\pi(x)+\\pi(y)?\\]", "tags": [ @@ -11738,27 +11676,6 @@ "comments_problem_id": 883, "comments_count": 3 }, - { - "problem_id": 884, - "problem_url": "/884", - "status_bucket": "open", - "status_dom_id": "open", - "status_label": "OPEN", - "status_detail": "This is open, and cannot be resolved with a finite computation.", - "prize_amount": "", - "statement": "Is it true that, for any $n$, if $d_1<\\cdots 2$ (and suppose that $k\\neq 2^l$ for any $l\\geq 1$) such that the leading coefficient of $f$ is positive. Does the set of integers $n\\geq 1$ for which $f(n)$ is $(k-1)$-power-free have positive density? If $k>3$ then are there infinitely many $n$ for which $f(n)$ is $(k-2)$-power-free? In particular, does\\[n^4+2\\]represent infinitely many squarefree numbers?", + "statement": "Let $f\\in \\mathbb{Z}[x]$ be an irreducible polynomial of degree $k>2$ (and suppose that $k\\neq 2^l$ for any $l\\geq 1$) such that the leading coefficient of $f$ is positive. Does the set of integers $n\\geq 1$ for which $f(n)$ is $(k-1)$-power-free have positive density? If $k>3$, and for all primes $p$ there exists $n$ such that $p^{k-2}\\nmid f(n)$, then are there infinitely many $n$ for which $f(n)$ is $(k-2)$-power-free? In particular, does\\[n^4+2\\]represent infinitely many squarefree numbers?", "tags": [ "number theory" ], - "last_edited": "05 March 2026", + "last_edited": "31 March 2026", "latex_path": "/latex/978", "formalized": true, "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/978.lean", "oeis_urls": [], "comments_problem_id": 978, - "comments_count": 8 + "comments_count": 16 }, { "problem_id": 979, @@ -13098,7 +13015,7 @@ "https://oeis.org/A219429" ], "comments_problem_id": 985, - "comments_count": 1 + "comments_count": 2 }, { "problem_id": 986, @@ -13183,7 +13100,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 993, - "comments_count": 1 + "comments_count": 2 }, { "problem_id": 995, @@ -13226,28 +13143,6 @@ "comments_problem_id": 996, "comments_count": 0 }, - { - "problem_id": 997, - "problem_url": "/997", - "status_bucket": "open", - "status_dom_id": "open", - "status_label": "OPEN", - "status_detail": "This is open, and cannot be resolved with a finite computation.", - "prize_amount": "", - "statement": "Call $x_1,x_2,\\ldots \\in (0,1)$ well-distributed if, for every $\\epsilon>0$, if $k$ is sufficiently large then, for all $n>0$ and intervals $I\\subseteq [0,1]$,\\[\\lvert \\# \\{ n0$ such that\\[\\lim_k \\frac{R(k+1,k)}{R(k,k)}> 1+c.\\]", + "statement": "Let $R(k,l)$ be the usual Ramsey number: the smallest $n$ such that if the edges of $K_n$ are coloured red and blue then there exists either a red $K_k$ or a blue $K_l$. Prove the existence of some $c>0$ such that\\[\\lim_{k\\to \\infty}\\frac{R(k+1,k)}{R(k,k)}> 1+c.\\]", "tags": [ "graph theory", "ramsey theory" ], - "last_edited": "03 December 2025", + "last_edited": "23 March 2026", "latex_path": "/latex/1030", "formalized": false, "formalized_url": "", @@ -13504,7 +13399,7 @@ "https://oeis.org/A059442" ], "comments_problem_id": 1030, - "comments_count": 1 + "comments_count": 2 }, { "problem_id": 1032, @@ -13585,7 +13480,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/1038.lean", "oeis_urls": [], "comments_problem_id": 1038, - "comments_count": 127 + "comments_count": 134 }, { "problem_id": 1039, @@ -13606,7 +13501,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 1039, - "comments_count": 1 + "comments_count": 9 }, { "problem_id": 1040, @@ -13626,7 +13521,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 1040, - "comments_count": 0 + "comments_count": 1 }, { "problem_id": 1041, @@ -13647,15 +13542,15 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/1041.lean", "oeis_urls": [], "comments_problem_id": 1041, - "comments_count": 2 + "comments_count": 41 }, { "problem_id": 1045, "problem_url": "/1045", "status_bucket": "open", "status_dom_id": "open", - "status_label": "FALSIFIABLE", - "status_detail": "Open, but could be disproved with a finite counterexample.", + "status_label": "OPEN", + "status_detail": "This is open, and cannot be resolved with a finite computation.", "prize_amount": "", "statement": "Let $z_1,\\ldots,z_n\\in \\mathbb{C}$ with $\\lvert z_i-z_j\\rvert\\leq 2$ for all $i,j$, and\\[\\Delta(z_1,\\ldots,z_n)=\\prod_{i\\neq j}\\lvert z_i-z_j\\rvert.\\]What is the maximum possible value of $\\Delta$? Is it maximised by taking the $z_i$ to be the vertices of a regular polygon?", "tags": [ @@ -13667,7 +13562,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 1045, - "comments_count": 43 + "comments_count": 45 }, { "problem_id": 1049, @@ -13687,7 +13582,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/1049.lean", "oeis_urls": [], "comments_problem_id": 1049, - "comments_count": 1 + "comments_count": 0 }, { "problem_id": 1052, @@ -14087,7 +13982,7 @@ "https://oeis.org/A064164" ], "comments_problem_id": 1074, - "comments_count": 3 + "comments_count": 5 }, { "problem_id": 1075, @@ -14362,7 +14257,7 @@ "https://oeis.org/A003458" ], "comments_problem_id": 1095, - "comments_count": 6 + "comments_count": 8 }, { "problem_id": 1096, @@ -14403,7 +14298,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/1097.lean", "oeis_urls": [], "comments_problem_id": 1097, - "comments_count": 11 + "comments_count": 17 }, { "problem_id": 1100, @@ -14468,7 +14363,7 @@ "https://oeis.org/A392164" ], "comments_problem_id": 1103, - "comments_count": 4 + "comments_count": 5 }, { "problem_id": 1104, @@ -14605,7 +14500,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 1110, - "comments_count": 3 + "comments_count": 4 }, { "problem_id": 1111, @@ -14728,7 +14623,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 1122, - "comments_count": 0 + "comments_count": 1 }, { "problem_id": 1131, @@ -14770,7 +14665,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 1132, - "comments_count": 1 + "comments_count": 2 }, { "problem_id": 1133, @@ -14904,7 +14799,7 @@ "https://oeis.org/A214583" ], "comments_problem_id": 1141, - "comments_count": 5 + "comments_count": 6 }, { "problem_id": 1142, @@ -14919,7 +14814,7 @@ "number theory", "primes" ], - "last_edited": "23 January 2026", + "last_edited": "05 March 2026", "latex_path": "/latex/1142", "formalized": true, "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/1142.lean", @@ -14927,7 +14822,7 @@ "https://oeis.org/A039669" ], "comments_problem_id": 1142, - "comments_count": 3 + "comments_count": 4 }, { "problem_id": 1143, @@ -15012,29 +14907,6 @@ "comments_problem_id": 1146, "comments_count": 0 }, - { - "problem_id": 1148, - "problem_url": "/1148", - "status_bucket": "open", - "status_dom_id": "open", - "status_label": "OPEN", - "status_detail": "This is open, and cannot be resolved with a finite computation.", - "prize_amount": "", - "statement": "Can every large integer $n$ be written as $n=x^2+y^2-z^2$ with $\\max(x^2,y^2,z^2)\\leq n$?", - "tags": [ - "number theory" - ], - "last_edited": "26 January 2026", - "latex_path": "/latex/1148", - "formalized": true, - "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/1148.lean", - "oeis_urls": [ - "https://oeis.org/A390380", - "https://oeis.org/A393168" - ], - "comments_problem_id": 1148, - "comments_count": 6 - }, { "problem_id": 1150, "problem_url": "/1150", @@ -15117,7 +14989,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 1153, - "comments_count": 7 + "comments_count": 10 }, { "problem_id": 1154, @@ -15456,8 +15328,8 @@ "problem_url": "/1174", "status_bucket": "open", "status_dom_id": "open", - "status_label": "OPEN", - "status_detail": "This is open, and cannot be resolved with a finite computation.", + "status_label": "NOT DISPROVABLE", + "status_detail": "Open in general, but there exist models of set theory where the result is true.", "prize_amount": "", "statement": "Does there exist a graph $G$ with no $K_4$ such that every edge colouring of $G$ with countably many colours contains a monochromatic $K_3$? Does there exist a graph $G$ with no $K_{\\aleph_1}$ such that every edge colouring of $G$ with countably many colours contains a monochromatic $K_{\\aleph_0}$?", "tags": [ @@ -15470,7 +15342,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 1174, - "comments_count": 1 + "comments_count": 2 }, { "problem_id": 1175, @@ -15498,8 +15370,8 @@ "problem_url": "/1176", "status_bucket": "open", "status_dom_id": "open", - "status_label": "OPEN", - "status_detail": "This is open, and cannot be resolved with a finite computation.", + "status_label": "NOT DISPROVABLE", + "status_detail": "Open in general, but there exist models of set theory where the result is true.", "prize_amount": "", "statement": "Let $G$ be a graph with chromatic number $\\aleph_1$. Is it true that there is a colouring of the edges with $\\aleph_1$ many colours such that, in any countable colouring of the vertices, there exists a vertex colour containing all edge colours?", "tags": [ @@ -15512,7 +15384,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/1176.lean", "oeis_urls": [], "comments_problem_id": 1176, - "comments_count": 0 + "comments_count": 1 }, { "problem_id": 1177, @@ -15556,6 +15428,68 @@ "oeis_urls": [], "comments_problem_id": 1178, "comments_count": 1 + }, + { + "problem_id": 1181, + "problem_url": "/1181", + "status_bucket": "open", + "status_dom_id": "open", + "status_label": "OPEN", + "status_detail": "This is open, and cannot be resolved with a finite computation.", + "prize_amount": "", + "statement": "Let $q(n,k)$ denote the least prime which does not divide $\\prod_{1\\leq i\\leq k}(n+i)$. Is it true that there exists some $c>0$ such that, for all large $n$,\\[q(n,\\log n)<(1-c)(\\log n)^2?\\]", + "tags": [ + "number theory" + ], + "last_edited": "07 March 2026", + "latex_path": "/latex/1181", + "formalized": false, + "formalized_url": "", + "oeis_urls": [], + "comments_problem_id": 1181, + "comments_count": 0 + }, + { + "problem_id": 1182, + "problem_url": "/1182", + "status_bucket": "open", + "status_dom_id": "open", + "status_label": "OPEN", + "status_detail": "This is open, and cannot be resolved with a finite computation.", + "prize_amount": "", + "statement": "Let $f(n)$ be maximal such that there is a connected graph $G$ with $n$ vertices and $f(n)$ edges such that\\[R(K_3,G)= 2n-1.\\]Let $F(n)$ be maximal such that every connected graph $G$ with $n$ vertices and $\\leq F(n)$ edges has\\[R(K_3,G)= 2n-1.\\]Estimate $f(n)$ and $F(n)$. In particular, is it true that $F(n)/n\\to \\infty$?", + "tags": [ + "graph theory", + "ramsey theory" + ], + "last_edited": "", + "latex_path": "/latex/1182", + "formalized": false, + "formalized_url": "", + "oeis_urls": [], + "comments_problem_id": 1182, + "comments_count": 3 + }, + { + "problem_id": 1183, + "problem_url": "/1183", + "status_bucket": "open", + "status_dom_id": "open", + "status_label": "OPEN", + "status_detail": "This is open, and cannot be resolved with a finite computation.", + "prize_amount": "", + "statement": "Let $f(n)$ be maximal such that in any $2$-colouring of the subsets of $\\{1,\\ldots,n\\}$ there is always a monochromatic family of at least $f(n)$ sets which is closed under taking unions and intersections. Estimate $f(n)$. Let $F(n)$ be defined similarly, except that we only require the family be closed under taking unions. Estimate $F(n)$. In particular, is it true that $F(n)\\geq n^{\\omega(n)}$ for some $\\omega(n)\\to \\infty$ as $n\\to \\infty$, and $F(n)<(1+o(1))^n$?", + "tags": [ + "combinatorics", + "ramsey theory" + ], + "last_edited": "", + "latex_path": "/latex/1183", + "formalized": false, + "formalized_url": "", + "oeis_urls": [], + "comments_problem_id": 1183, + "comments_count": 10 } ] } diff --git a/packs/erdos-open-problems/data/erdos_problems.all.json b/packs/erdos-open-problems/data/erdos_problems.all.json index 2570e3c..5cd682e 100644 --- a/packs/erdos-open-problems/data/erdos_problems.all.json +++ b/packs/erdos-open-problems/data/erdos_problems.all.json @@ -2,35 +2,35 @@ "schema_version": "1.0.0", "subset": "all", "active_status": "open", - "generated_at_utc": "2026-03-05T15:52:31Z", + "generated_at_utc": "2026-04-01T06:51:20Z", "source": { "site": "erdosproblems.com", "url": "https://erdosproblems.com/range/1-end", - "source_sha256": "72366d21b9530355396bef95b3ead90176a9c634b7ecd68fd30c85bad703a0c1", + "source_sha256": "870c67de08d4d2a7667ad4a3cd9b930d3a9809cca047a50fa20ab5b2b22fc23d", "solve_count": { - "raw": "488 solved out of 1179 shown", - "solved": 488, - "shown": 1179 + "raw": "495 solved out of 1183 shown", + "solved": 495, + "shown": 1183 } }, "summary": { - "total": 1179, - "open": 691, - "closed": 488, + "total": 1183, + "open": 688, + "closed": 495, "unknown": 0, "status_label_counts": { "DECIDABLE": 9, "DISPROVED": 76, - "DISPROVED (LEAN)": 40, - "FALSIFIABLE": 29, + "DISPROVED (LEAN)": 43, + "FALSIFIABLE": 27, "INDEPENDENT": 3, - "NOT DISPROVABLE": 2, + "NOT DISPROVABLE": 4, "NOT PROVABLE": 4, - "OPEN": 645, - "PROVED": 239, - "PROVED (LEAN)": 63, - "SOLVED": 52, - "SOLVED (LEAN)": 10, + "OPEN": 640, + "PROVED": 238, + "PROVED (LEAN)": 70, + "SOLVED": 51, + "SOLVED (LEAN)": 11, "VERIFIABLE": 7 } }, @@ -1213,7 +1213,11 @@ 1176, 1177, 1178, - 1179 + 1179, + 1180, + 1181, + 1182, + 1183 ], "problems": [ { @@ -1453,8 +1457,8 @@ "problem_url": "/11", "status_bucket": "open", "status_dom_id": "open", - "status_label": "FALSIFIABLE", - "status_detail": "Open, but could be disproved with a finite counterexample.", + "status_label": "OPEN", + "status_detail": "This is open, and cannot be resolved with a finite computation.", "prize_amount": "", "statement": "Is every large odd integer $n$ the sum of a squarefree number and a power of 2?", "tags": [ @@ -1622,8 +1626,8 @@ ], "last_edited": "20 January 2026", "latex_path": "/latex/18", - "formalized": false, - "formalized_url": "", + "formalized": true, + "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/18.lean", "oeis_urls": [ "https://oeis.org/A005153" ], @@ -1643,7 +1647,7 @@ "graph theory", "chromatic number" ], - "last_edited": "23 January 2026", + "last_edited": "07 March 2026", "latex_path": "/latex/19", "formalized": false, "formalized_url": "", @@ -1663,7 +1667,7 @@ "tags": [ "combinatorics" ], - "last_edited": "25 January 2026", + "last_edited": "07 March 2026", "latex_path": "/latex/20", "formalized": true, "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/20.lean", @@ -1776,7 +1780,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/25.lean", "oeis_urls": [], "comments_problem_id": 25, - "comments_count": 2 + "comments_count": 7 }, { "problem_id": 26, @@ -1949,7 +1953,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/33.lean", "oeis_urls": [], "comments_problem_id": 33, - "comments_count": 4 + "comments_count": 5 }, { "problem_id": 34, @@ -2318,8 +2322,8 @@ ], "last_edited": "", "latex_path": "/latex/50", - "formalized": false, - "formalized_url": "", + "formalized": true, + "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/50.lean", "oeis_urls": [], "comments_problem_id": 50, "comments_count": 0 @@ -2360,7 +2364,7 @@ "number theory", "additive combinatorics" ], - "last_edited": "23 January 2026", + "last_edited": "23 March 2026", "latex_path": "/latex/52", "formalized": false, "formalized_url": "", @@ -3065,8 +3069,8 @@ "problem_url": "/85", "status_bucket": "open", "status_dom_id": "open", - "status_label": "FALSIFIABLE", - "status_detail": "Open, but could be disproved with a finite counterexample.", + "status_label": "OPEN", + "status_detail": "This is open, and cannot be resolved with a finite computation.", "prize_amount": "", "statement": "Let $n\\geq 4$ and $f(n)$ be minimal such that every graph on $n$ vertices with minimal degree $\\geq f(n)$ contains a $C_4$. Is it true that, for all large $n$, $f(n+1)\\geq f(n)$?", "tags": [ @@ -3217,7 +3221,7 @@ "https://oeis.org/A186704" ], "comments_problem_id": 91, - "comments_count": 5 + "comments_count": 6 }, { "problem_id": 92, @@ -3532,7 +3536,7 @@ "tags": [ "geometry" ], - "last_edited": "", + "last_edited": "06 March 2026", "latex_path": "/latex/106", "formalized": false, "formalized_url": "", @@ -3696,8 +3700,8 @@ "problem_url": "/114", "status_bucket": "open", "status_dom_id": "open", - "status_label": "OPEN", - "status_detail": "This is open, and cannot be resolved with a finite computation.", + "status_label": "FALSIFIABLE", + "status_detail": "Open, but could be disproved with a finite counterexample.", "prize_amount": "$250", "statement": "If $p(z)\\in\\mathbb{C}[z]$ is a monic polynomial of degree $n$ then is the length of the curve $\\{ z\\in \\mathbb{C} : \\lvert p(z)\\rvert=1\\}$ maximised when $p(z)=z^n-1$?", "tags": [ @@ -3710,7 +3714,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 114, - "comments_count": 3 + "comments_count": 4 }, { "problem_id": 115, @@ -3834,7 +3838,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/120.lean", "oeis_urls": [], "comments_problem_id": 120, - "comments_count": 1 + "comments_count": 3 }, { "problem_id": 121, @@ -3884,7 +3888,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 122, - "comments_count": 0 + "comments_count": 3 }, { "problem_id": 123, @@ -3931,17 +3935,17 @@ { "problem_id": 125, "problem_url": "/125", - "status_bucket": "open", - "status_dom_id": "open", - "status_label": "OPEN", - "status_detail": "This is open, and cannot be resolved with a finite computation.", + "status_bucket": "closed", + "status_dom_id": "solved", + "status_label": "DISPROVED (LEAN)", + "status_detail": "This has been solved in the negative and the proof verified in Lean.", "prize_amount": "", - "statement": "Let $A = \\{ \\sum\\epsilon_k3^k : \\epsilon_k\\in \\{0,1\\}\\}$ be the set of integers which have only the digits $0,1$ when written base $3$, and $B=\\{ \\sum\\epsilon_k4^k : \\epsilon_k\\in \\{0,1\\}\\}$ be the set of integers which have only the digits $0,1$ when written base $4$. Does $A+B$ have positive density?", + "statement": "Let $A = \\{ \\sum\\epsilon_k3^k : \\epsilon_k\\in \\{0,1\\}\\}$ be the set of integers which have only the digits $0,1$ when written base $3$, and $B=\\{ \\sum\\epsilon_k4^k : \\epsilon_k\\in \\{0,1\\}\\}$ be the set of integers which have only the digits $0,1$ when written base $4$. Does $A+B$ have positive lower density?", "tags": [ "number theory", "base representations" ], - "last_edited": "", + "last_edited": "30 March 2026", "latex_path": "/latex/125", "formalized": true, "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/125.lean", @@ -3949,7 +3953,7 @@ "https://oeis.org/A367090" ], "comments_problem_id": 125, - "comments_count": 13 + "comments_count": 21 }, { "problem_id": 126, @@ -4474,8 +4478,8 @@ "problem_url": "/150", "status_bucket": "closed", "status_dom_id": "solved", - "status_label": "PROVED", - "status_detail": "This has been solved in the affirmative.", + "status_label": "PROVED (LEAN)", + "status_detail": "This has been solved in the affirmative and the proof verified in Lean.", "prize_amount": "", "statement": "A minimal cut of a graph is a minimal set of vertices whose removal disconnects the graph. Let $c(n)$ be the maximum number of minimal cuts a graph on $n$ vertices can have. Does $c(n)^{1/n}\\to \\alpha$ for some $\\alpha <2$?", "tags": [ @@ -4487,7 +4491,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 150, - "comments_count": 0 + "comments_count": 1 }, { "problem_id": 151, @@ -4663,13 +4667,13 @@ "status_dom_id": "open", "status_label": "OPEN", "status_detail": "This is open, and cannot be resolved with a finite computation.", - "prize_amount": "", + "prize_amount": "$100", "statement": "There exists some constant $c>0$ such that $$R(C_4,K_n) \\ll n^{2-c}.$$", "tags": [ "graph theory", "ramsey theory" ], - "last_edited": "", + "last_edited": "07 March 2026", "latex_path": "/latex/159", "formalized": false, "formalized_url": "", @@ -4800,7 +4804,7 @@ "graph theory", "ramsey theory" ], - "last_edited": "28 December 2025", + "last_edited": "07 March 2026", "latex_path": "/latex/165", "formalized": false, "formalized_url": "", @@ -4865,7 +4869,7 @@ "tags": [ "additive combinatorics" ], - "last_edited": "24 October 2025", + "last_edited": "23 March 2026", "latex_path": "/latex/168", "formalized": true, "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/168.lean", @@ -5050,7 +5054,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 176, - "comments_count": 1 + "comments_count": 3 }, { "problem_id": 177, @@ -5163,12 +5167,12 @@ "status_dom_id": "solved", "status_label": "PROVED", "status_detail": "This has been solved in the affirmative.", - "prize_amount": "", + "prize_amount": "$100", "statement": "Let $k\\geq 3$. What is the maximum number of edges that a graph on $n$ vertices can contain if it does not have a $k$-regular subgraph? Is it $\\ll n^{1+o(1)}$?", "tags": [ "graph theory" ], - "last_edited": "23 January 2026", + "last_edited": "07 March 2026", "latex_path": "/latex/182", "formalized": false, "formalized_url": "", @@ -5214,11 +5218,11 @@ ], "last_edited": "", "latex_path": "/latex/184", - "formalized": false, - "formalized_url": "", + "formalized": true, + "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/184.lean", "oeis_urls": [], "comments_problem_id": 184, - "comments_count": 0 + "comments_count": 1 }, { "problem_id": 185, @@ -5405,8 +5409,8 @@ ], "last_edited": "", "latex_path": "/latex/193", - "formalized": false, - "formalized_url": "", + "formalized": true, + "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/193.lean", "oeis_urls": [ "https://oeis.org/A231255" ], @@ -5632,8 +5636,8 @@ "problem_url": "/204", "status_bucket": "closed", "status_dom_id": "solved", - "status_label": "DISPROVED", - "status_detail": "This has been solved in the negative.", + "status_label": "DISPROVED (LEAN)", + "status_detail": "This has been solved in the negative and the proof verified in Lean.", "prize_amount": "", "statement": "Are there $n$ such that there is a covering system with moduli the divisors of $n$ which is 'as disjoint as possible'? That is, for all $d\\mid n$ with $d>1$ there is an associated $a_d$ such that every integer is congruent to some $a_d\\pmod{d}$, and if there is some integer $x$ with\\[x\\equiv a_d\\pmod{d}\\textrm{ and }x\\equiv a_{d'}\\pmod{d'}\\]then $(d,d')=1$.", "tags": [ @@ -5646,7 +5650,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/204.lean", "oeis_urls": [], "comments_problem_id": 204, - "comments_count": 0 + "comments_count": 1 }, { "problem_id": 205, @@ -6015,7 +6019,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 221, - "comments_count": 2 + "comments_count": 4 }, { "problem_id": 222, @@ -6093,7 +6097,7 @@ "tags": [ "analysis" ], - "last_edited": "01 February 2026", + "last_edited": "05 March 2026", "latex_path": "/latex/225", "formalized": false, "formalized_url": "", @@ -6437,7 +6441,7 @@ "https://oeis.org/A387704" ], "comments_problem_id": 241, - "comments_count": 2 + "comments_count": 3 }, { "problem_id": 242, @@ -6488,7 +6492,7 @@ "https://oeis.org/A000058" ], "comments_problem_id": 243, - "comments_count": 6 + "comments_count": 7 }, { "problem_id": 244, @@ -6719,8 +6723,8 @@ ], "last_edited": "07 December 2025", "latex_path": "/latex/254", - "formalized": false, - "formalized_url": "", + "formalized": true, + "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/254.lean", "oeis_urls": [], "comments_problem_id": 254, "comments_count": 3 @@ -6841,8 +6845,8 @@ ], "last_edited": "01 February 2026", "latex_path": "/latex/260", - "formalized": false, - "formalized_url": "", + "formalized": true, + "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/260.lean", "oeis_urls": [], "comments_problem_id": 260, "comments_count": 2 @@ -7133,7 +7137,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/274.lean", "oeis_urls": [], "comments_problem_id": 274, - "comments_count": 2 + "comments_count": 3 }, { "problem_id": 275, @@ -7325,7 +7329,7 @@ "https://oeis.org/A380791" ], "comments_problem_id": 283, - "comments_count": 2 + "comments_count": 3 }, { "problem_id": 284, @@ -7642,7 +7646,7 @@ "number theory", "unit fractions" ], - "last_edited": "23 January 2026", + "last_edited": "31 March 2026", "latex_path": "/latex/298", "formalized": true, "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/298.lean", @@ -7994,7 +7998,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 314, - "comments_count": 1 + "comments_count": 3 }, { "problem_id": 315, @@ -8190,8 +8194,8 @@ ], "last_edited": "", "latex_path": "/latex/323", - "formalized": false, - "formalized_url": "", + "formalized": true, + "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/323.lean", "oeis_urls": [], "comments_problem_id": 323, "comments_count": 0 @@ -8236,7 +8240,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/325.lean", "oeis_urls": [], "comments_problem_id": 325, - "comments_count": 0 + "comments_count": 2 }, { "problem_id": 326, @@ -8257,7 +8261,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/326.lean", "oeis_urls": [], "comments_problem_id": 326, - "comments_count": 2 + "comments_count": 3 }, { "problem_id": 327, @@ -8337,7 +8341,7 @@ "number theory", "additive basis" ], - "last_edited": "08 December 2025", + "last_edited": "31 March 2026", "latex_path": "/latex/330", "formalized": true, "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/330.lean", @@ -8423,7 +8427,10 @@ "latex_path": "/latex/334", "formalized": false, "formalized_url": "", - "oeis_urls": [], + "oeis_urls": [ + "https://oeis.org/A045535", + "https://oeis.org/A062241" + ], "comments_problem_id": 334, "comments_count": 2 }, @@ -8592,13 +8599,13 @@ ], "last_edited": "30 September 2025", "latex_path": "/latex/342", - "formalized": false, - "formalized_url": "", + "formalized": true, + "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/342.lean", "oeis_urls": [ "https://oeis.org/A002858" ], "comments_problem_id": 342, - "comments_count": 11 + "comments_count": 18 }, { "problem_id": 343, @@ -8747,7 +8754,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/349.lean", "oeis_urls": [], "comments_problem_id": 349, - "comments_count": 8 + "comments_count": 12 }, { "problem_id": 350, @@ -8871,7 +8878,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/355.lean", "oeis_urls": [], "comments_problem_id": 355, - "comments_count": 16 + "comments_count": 18 }, { "problem_id": 356, @@ -8936,7 +8943,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/358.lean", "oeis_urls": [], "comments_problem_id": 358, - "comments_count": 19 + "comments_count": 21 }, { "problem_id": 359, @@ -9025,8 +9032,8 @@ "problem_url": "/363", "status_bucket": "closed", "status_dom_id": "solved", - "status_label": "DISPROVED", - "status_detail": "This has been solved in the negative.", + "status_label": "DISPROVED (LEAN)", + "status_detail": "This has been solved in the negative and the proof verified in Lean.", "prize_amount": "", "statement": "Is it true that there are only finitely many collections of disjoint intervals $I_1,\\ldots,I_n$ of size $\\lvert I_i\\rvert \\geq 4$ for $1\\leq i\\leq n$ such that\\[\\prod_{1\\leq i\\leq n}\\prod_{m\\in I_i}m\\]is a square?", "tags": [ @@ -9038,7 +9045,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 363, - "comments_count": 1 + "comments_count": 2 }, { "problem_id": 364, @@ -9087,7 +9094,7 @@ "https://oeis.org/A175155" ], "comments_problem_id": 365, - "comments_count": 2 + "comments_count": 3 }, { "problem_id": 366, @@ -9097,12 +9104,12 @@ "status_label": "VERIFIABLE", "status_detail": "Open, but could be proved with a finite example.", "prize_amount": "", - "statement": "Are there any 2-full $n$ such that $n+1$ is 3-full? That is, if $p\\mid n$ then $p^2\\mid n$ and if $p\\mid n+1$ then $p^3\\mid n+1$.", + "statement": "Are there any $2$-full $n$ such that $n+1$ is $3$-full? That is, if $p\\mid n$ then $p^2\\mid n$ and if $p\\mid n+1$ then $p^3\\mid n+1$.", "tags": [ "number theory", "powerful" ], - "last_edited": "20 December 2025", + "last_edited": "23 March 2026", "latex_path": "/latex/366", "formalized": true, "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/366.lean", @@ -9120,12 +9127,12 @@ "status_label": "OPEN", "status_detail": "This is open, and cannot be resolved with a finite computation.", "prize_amount": "", - "statement": "Let $B_2(n)$ be the 2-full part of $n$ (that is, $B_2(n)=n/n'$ where $n'$ is the product of all primes that divide $n$ exactly once). Is it true that, for every fixed $k\\geq 1$,\\[\\prod_{n\\leq m0$ and $k\\geq 2$. Is it true that, for all sufficiently large $n$, there is a sequence of $k$ consecutive integers in $\\{1,\\ldots,n\\}$ all of which are $n^\\epsilon$-smooth?", "tags": [ @@ -9175,7 +9182,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 369, - "comments_count": 0 + "comments_count": 11 }, { "problem_id": 370, @@ -9287,7 +9294,7 @@ "https://oeis.org/A389148" ], "comments_problem_id": 374, - "comments_count": 0 + "comments_count": 1 }, { "problem_id": 375, @@ -9402,8 +9409,8 @@ "problem_url": "/380", "status_bucket": "open", "status_dom_id": "open", - "status_label": "OPEN", - "status_detail": "This is open, and cannot be resolved with a finite computation.", + "status_label": "PROVED", + "status_detail": "This has been solved in the affirmative.", "prize_amount": "", "statement": "We call an interval $[u,v]$ 'bad' if the greatest prime factor of $\\prod_{u\\leq m\\leq v}m$ occurs with an exponent greater than $1$. Let $B(x)$ count the number of $n\\leq x$ which are contained in at least one bad interval. Is it true that\\[B(x)\\sim \\#\\{ n\\leq x: P(n)^2\\mid n\\},\\]where $P(n)$ is the largest prime factor of $n$?", "tags": [ @@ -9420,7 +9427,7 @@ "https://oeis.org/A389100" ], "comments_problem_id": 380, - "comments_count": 5 + "comments_count": 9 }, { "problem_id": 381, @@ -9551,7 +9558,7 @@ "https://oeis.org/A280992" ], "comments_problem_id": 386, - "comments_count": 12 + "comments_count": 13 }, { "problem_id": 387, @@ -9592,7 +9599,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 388, - "comments_count": 5 + "comments_count": 10 }, { "problem_id": 389, @@ -9614,7 +9621,7 @@ "https://oeis.org/A375071" ], "comments_problem_id": 389, - "comments_count": 6 + "comments_count": 8 }, { "problem_id": 390, @@ -9770,7 +9777,7 @@ "https://oeis.org/A375077" ], "comments_problem_id": 396, - "comments_count": 1 + "comments_count": 30 }, { "problem_id": 397, @@ -9806,15 +9813,16 @@ "number theory", "factorials" ], - "last_edited": "", + "last_edited": "01 April 2026", "latex_path": "/latex/398", "formalized": true, "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/398.lean", "oeis_urls": [ + "https://oeis.org/A141399", "https://oeis.org/A146968" ], "comments_problem_id": 398, - "comments_count": 6 + "comments_count": 9 }, { "problem_id": 399, @@ -9852,8 +9860,8 @@ ], "last_edited": "", "latex_path": "/latex/400", - "formalized": false, - "formalized_url": "", + "formalized": true, + "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/400.lean", "oeis_urls": [], "comments_problem_id": 400, "comments_count": 0 @@ -10354,7 +10362,7 @@ "tags": [ "number theory" ], - "last_edited": "16 January 2026", + "last_edited": "23 March 2026", "latex_path": "/latex/423", "formalized": false, "formalized_url": "", @@ -10362,7 +10370,7 @@ "https://oeis.org/A005243" ], "comments_problem_id": 423, - "comments_count": 18 + "comments_count": 38 }, { "problem_id": 424, @@ -10376,7 +10384,7 @@ "tags": [ "number theory" ], - "last_edited": "", + "last_edited": "31 March 2026", "latex_path": "/latex/424", "formalized": true, "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/424.lean", @@ -10814,8 +10822,8 @@ ], "last_edited": "27 December 2025", "latex_path": "/latex/445", - "formalized": false, - "formalized_url": "", + "formalized": true, + "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/445.lean", "oeis_urls": [], "comments_problem_id": 445, "comments_count": 1 @@ -11055,16 +11063,16 @@ { "problem_id": 457, "problem_url": "/457", - "status_bucket": "open", - "status_dom_id": "open", - "status_label": "OPEN", - "status_detail": "This is open, and cannot be resolved with a finite computation.", + "status_bucket": "closed", + "status_dom_id": "solved", + "status_label": "PROVED (LEAN)", + "status_detail": "This has been solved in the affirmative and the proof verified in Lean.", "prize_amount": "", "statement": "Is there some $\\epsilon>0$ such that there are infinitely many $n$ where all primes $p\\leq (2+\\epsilon)\\log n$ divide\\[\\prod_{1\\leq i\\leq \\log n}(n+i)?\\]", "tags": [ "number theory" ], - "last_edited": "07 October 2025", + "last_edited": "07 March 2026", "latex_path": "/latex/457", "formalized": true, "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/457.lean", @@ -11072,7 +11080,7 @@ "https://oeis.org/A391668" ], "comments_problem_id": 457, - "comments_count": 7 + "comments_count": 10 }, { "problem_id": 458, @@ -11102,8 +11110,8 @@ "problem_url": "/459", "status_bucket": "closed", "status_dom_id": "solved", - "status_label": "SOLVED", - "status_detail": "This has been resolved in some other way than a proof or disproof.", + "status_label": "SOLVED (LEAN)", + "status_detail": "This has been resolved in some other way than a proof or disproof, and that resolution verified in Lean.", "prize_amount": "", "statement": "Let $f(u)$ be the largest $v$ such that no $m\\in (u,v)$ is composed entirely of primes dividing $uv$. Estimate $f(u)$.", "tags": [ @@ -11118,7 +11126,7 @@ "https://oeis.org/A289280" ], "comments_problem_id": 459, - "comments_count": 2 + "comments_count": 3 }, { "problem_id": 460, @@ -11456,7 +11464,7 @@ "number theory", "additive combinatorics" ], - "last_edited": "", + "last_edited": "05 March 2026", "latex_path": "/latex/475", "formalized": false, "formalized_url": "", @@ -11731,8 +11739,8 @@ "problem_url": "/488", "status_bucket": "open", "status_dom_id": "open", - "status_label": "OPEN", - "status_detail": "This is open, and cannot be resolved with a finite computation.", + "status_label": "FALSIFIABLE", + "status_detail": "Open, but could be disproved with a finite counterexample.", "prize_amount": "", "statement": "Let $A$ be a finite set and\\[B=\\{ n \\geq 1 : a\\mid n\\textrm{ for some }a\\in A\\}.\\]Is it true that, for every $m>n\\geq \\max(A)$,\\[\\frac{\\lvert B\\cap [1,m]\\rvert }{m}< 2\\frac{\\lvert B\\cap [1,n]\\rvert}{n}?\\]", "tags": [ @@ -11744,7 +11752,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/488.lean", "oeis_urls": [], "comments_problem_id": 488, - "comments_count": 14 + "comments_count": 27 }, { "problem_id": 489, @@ -11865,7 +11873,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/494.lean", "oeis_urls": [], "comments_problem_id": 494, - "comments_count": 2 + "comments_count": 3 }, { "problem_id": 495, @@ -12343,7 +12351,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/517.lean", "oeis_urls": [], "comments_problem_id": 517, - "comments_count": 0 + "comments_count": 1 }, { "problem_id": 518, @@ -12824,7 +12832,7 @@ "tags": [ "number theory" ], - "last_edited": "28 December 2025", + "last_edited": "06 March 2026", "latex_path": "/latex/540", "formalized": false, "formalized_url": "", @@ -12990,12 +12998,12 @@ "status_dom_id": "open", "status_label": "FALSIFIABLE", "status_detail": "Open, but could be disproved with a finite counterexample.", - "prize_amount": "", + "prize_amount": "$100", "statement": "Let $n\\geq k+1$. Every graph on $n$ vertices with at least $\\frac{k-1}{2}n+1$ edges contains every tree on $k+1$ vertices.", "tags": [ "graph theory" ], - "last_edited": "23 January 2026", + "last_edited": "07 March 2026", "latex_path": "/latex/548", "formalized": false, "formalized_url": "", @@ -13451,7 +13459,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 569, - "comments_count": 0 + "comments_count": 2 }, { "problem_id": 570, @@ -13487,7 +13495,7 @@ "graph theory", "turan number" ], - "last_edited": "18 January 2026", + "last_edited": "07 March 2026", "latex_path": "/latex/571", "formalized": false, "formalized_url": "", @@ -13545,8 +13553,8 @@ "problem_url": "/574", "status_bucket": "open", "status_dom_id": "open", - "status_label": "OPEN", - "status_detail": "This is open, and cannot be resolved with a finite computation.", + "status_label": "DISPROVED", + "status_detail": "This has been solved in the negative.", "prize_amount": "", "statement": "Is it true that, for $k\\geq 2$,\\[\\mathrm{ex}(n;\\{C_{2k-1},C_{2k}\\})=(1+o(1))(n/2)^{1+\\frac{1}{k}}.\\]", "tags": [ @@ -13559,7 +13567,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 574, - "comments_count": 0 + "comments_count": 1 }, { "problem_id": 575, @@ -13743,7 +13751,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 583, - "comments_count": 1 + "comments_count": 3 }, { "problem_id": 584, @@ -14061,7 +14069,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/598.lean", "oeis_urls": [], "comments_problem_id": 598, - "comments_count": 0 + "comments_count": 2 }, { "problem_id": 599, @@ -14180,7 +14188,7 @@ "geometry", "distances" ], - "last_edited": "15 October 2025", + "last_edited": "23 March 2026", "latex_path": "/latex/604", "formalized": false, "formalized_url": "", @@ -14450,7 +14458,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/617.lean", "oeis_urls": [], "comments_problem_id": 617, - "comments_count": 0 + "comments_count": 1 }, { "problem_id": 618, @@ -14779,7 +14787,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 633, - "comments_count": 2 + "comments_count": 5 }, { "problem_id": 634, @@ -15119,22 +15127,24 @@ { "problem_id": 650, "problem_url": "/650", - "status_bucket": "open", - "status_dom_id": "open", - "status_label": "OPEN", - "status_detail": "This is open, and cannot be resolved with a finite computation.", + "status_bucket": "closed", + "status_dom_id": "solved", + "status_label": "PROVED (LEAN)", + "status_detail": "This has been solved in the affirmative and the proof verified in Lean.", "prize_amount": "", - "statement": "Let $f(m)$ be such that if $A\\subseteq \\{1,\\ldots,N\\}$ has $\\lvert A\\rvert=m$ then every interval in $[1,\\infty)$ of length $2N$ contains $\\geq f(m)$ many distinct integers $b_1,\\ldots,b_r$ where each $b_i$ is divisible by some $a_i\\in A$, where $a_1,\\ldots,a_r$ are distinct. Estimate $f(m)$. In particular is it true that $f(m)\\ll m^{1/2}$?", + "statement": "Let $f(m)$ be such that if $A\\subseteq \\{1,\\ldots,N\\}$ has $\\lvert A\\rvert=m$ then every interval in $[1,\\infty)$ of length $2N$ contains $\\geq f(m)$ many distinct integers $b_1,\\ldots,b_r$ where each $b_i$ is divisible by some $a_i\\in A$, where $a_1,\\ldots,a_r$ are distinct. Estimate $f(m)$. In particular is it true that $f(m)\\leq \\sqrt{m}$?", "tags": [ "number theory" ], - "last_edited": "", + "last_edited": "01 April 2026", "latex_path": "/latex/650", "formalized": false, "formalized_url": "", - "oeis_urls": [], + "oeis_urls": [ + "https://oeis.org/A027434" + ], "comments_problem_id": 650, - "comments_count": 0 + "comments_count": 28 }, { "problem_id": 651, @@ -15698,7 +15708,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/677.lean", "oeis_urls": [], "comments_problem_id": 677, - "comments_count": 0 + "comments_count": 7 }, { "problem_id": 678, @@ -15823,8 +15833,8 @@ ], "last_edited": "31 December 2025", "latex_path": "/latex/683", - "formalized": false, - "formalized_url": "", + "formalized": true, + "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/683.lean", "oeis_urls": [ "https://oeis.org/A006530", "https://oeis.org/A074399", @@ -15847,7 +15857,7 @@ "primes", "binomial coefficients" ], - "last_edited": "23 January 2026", + "last_edited": "01 April 2026", "latex_path": "/latex/684", "formalized": false, "formalized_url": "", @@ -15897,7 +15907,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/686.lean", "oeis_urls": [], "comments_problem_id": 686, - "comments_count": 16 + "comments_count": 37 }, { "problem_id": 687, @@ -16278,7 +16288,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 704, - "comments_count": 1 + "comments_count": 4 }, { "problem_id": 705, @@ -16375,13 +16385,13 @@ "tags": [ "number theory" ], - "last_edited": "", + "last_edited": "23 March 2026", "latex_path": "/latex/709", "formalized": false, "formalized_url": "", "oeis_urls": [], "comments_problem_id": 709, - "comments_count": 0 + "comments_count": 2 }, { "problem_id": 710, @@ -16460,7 +16470,7 @@ "graph theory", "turan number" ], - "last_edited": "06 October 2025", + "last_edited": "07 March 2026", "latex_path": "/latex/713", "formalized": false, "formalized_url": "", @@ -16604,7 +16614,7 @@ "graph theory", "ramsey theory" ], - "last_edited": "26 October 2025", + "last_edited": "07 March 2026", "latex_path": "/latex/720", "formalized": false, "formalized_url": "", @@ -16654,7 +16664,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 722, - "comments_count": 0 + "comments_count": 1 }, { "problem_id": 723, @@ -16784,7 +16794,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/728.lean", "oeis_urls": [], "comments_problem_id": 728, - "comments_count": 84 + "comments_count": 86 }, { "problem_id": 729, @@ -17048,17 +17058,17 @@ "status_label": "OPEN", "status_detail": "This is open, and cannot be resolved with a finite computation.", "prize_amount": "", - "statement": "Let $A\\subseteq \\mathbb{N}$ be such that $A+A$ has positive density. Can one always decompose $A=A_1\\sqcup A_2$ such that $A_1+A_1$ and $A_2+A_2$ both have positive density? Is there a basis $A$ of order $2$ such that if $A=A_1\\sqcup A_2$ then $A_1+A_1$ and $A_2+A_2$ cannot both have bounded gaps?", + "statement": "Let $A\\subseteq \\mathbb{N}$ be such that $A+A$ has positive (upper) density. Can one always decompose $A=A_1\\sqcup A_2$ such that $A_1+A_1$ and $A_2+A_2$ both have positive (upper) density? Is there a basis $A$ of order $2$ such that if $A=A_1\\sqcup A_2$ then $A_1+A_1$ and $A_2+A_2$ cannot both have bounded gaps?", "tags": [ "additive combinatorics" ], - "last_edited": "", + "last_edited": "01 April 2026", "latex_path": "/latex/741", "formalized": true, "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/741.lean", "oeis_urls": [], "comments_problem_id": 741, - "comments_count": 0 + "comments_count": 3 }, { "problem_id": 742, @@ -17354,8 +17364,8 @@ "problem_url": "/756", "status_bucket": "closed", "status_dom_id": "solved", - "status_label": "PROVED", - "status_detail": "This has been solved in the affirmative.", + "status_label": "PROVED (LEAN)", + "status_detail": "This has been solved in the affirmative and the proof verified in Lean.", "prize_amount": "", "statement": "Let $A\\subset \\mathbb{R}^2$ be a set of $n$ points. Can there be $\\gg n$ many distinct distances each of which occurs for more than $n$ many pairs from $A$?", "tags": [ @@ -17368,7 +17378,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 756, - "comments_count": 0 + "comments_count": 1 }, { "problem_id": 757, @@ -17968,20 +17978,20 @@ "problem_url": "/785", "status_bucket": "closed", "status_dom_id": "solved", - "status_label": "PROVED", - "status_detail": "This has been solved in the affirmative.", + "status_label": "PROVED (LEAN)", + "status_detail": "This has been solved in the affirmative and the proof verified in Lean.", "prize_amount": "", "statement": "Let $A,B\\subseteq \\mathbb{N}$ be infinite sets such that $A+B$ contains all large integers. Let $A(x)=\\lvert A\\cap [1,x]\\rvert$ and similarly for $B(x)$. Is it true that if $A(x)B(x)\\sim x$ then\\[A(x)B(x)-x\\to \\infty\\]as $x\\to \\infty$?", "tags": [ "additive combinatorics" ], - "last_edited": "", + "last_edited": "07 March 2026", "latex_path": "/latex/785", "formalized": false, "formalized_url": "", "oeis_urls": [], "comments_problem_id": 785, - "comments_count": 2 + "comments_count": 5 }, { "problem_id": 786, @@ -18473,7 +18483,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 809, - "comments_count": 0 + "comments_count": 1 }, { "problem_id": 810, @@ -18532,8 +18542,8 @@ ], "last_edited": "", "latex_path": "/latex/812", - "formalized": false, - "formalized_url": "", + "formalized": true, + "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/812.lean", "oeis_urls": [], "comments_problem_id": 812, "comments_count": 0 @@ -19016,7 +19026,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/835.lean", "oeis_urls": [], "comments_problem_id": 835, - "comments_count": 4 + "comments_count": 5 }, { "problem_id": 836, @@ -19285,7 +19295,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/848.lean", "oeis_urls": [], "comments_problem_id": 848, - "comments_count": 18 + "comments_count": 47 }, { "problem_id": 849, @@ -19406,7 +19416,7 @@ "https://oeis.org/A390769" ], "comments_problem_id": 853, - "comments_count": 2 + "comments_count": 3 }, { "problem_id": 854, @@ -19436,8 +19446,8 @@ "problem_url": "/855", "status_bucket": "open", "status_dom_id": "open", - "status_label": "FALSIFIABLE", - "status_detail": "Open, but could be disproved with a finite counterexample.", + "status_label": "OPEN", + "status_detail": "This is open, and cannot be resolved with a finite computation.", "prize_amount": "", "statement": "If $\\pi(x)$ counts the number of primes in $[1,x]$ then is it true that (for large $x$ and $y$)\\[\\pi(x+y) \\leq \\pi(x)+\\pi(y)?\\]", "tags": [ @@ -20054,23 +20064,23 @@ { "problem_id": 884, "problem_url": "/884", - "status_bucket": "open", - "status_dom_id": "open", - "status_label": "OPEN", - "status_detail": "This is open, and cannot be resolved with a finite computation.", + "status_bucket": "closed", + "status_dom_id": "solved", + "status_label": "DISPROVED", + "status_detail": "This has been solved in the negative.", "prize_amount": "", "statement": "Is it true that, for any $n$, if $d_1<\\cdots 2$ (and suppose that $k\\neq 2^l$ for any $l\\geq 1$) such that the leading coefficient of $f$ is positive. Does the set of integers $n\\geq 1$ for which $f(n)$ is $(k-1)$-power-free have positive density? If $k>3$ then are there infinitely many $n$ for which $f(n)$ is $(k-2)$-power-free? In particular, does\\[n^4+2\\]represent infinitely many squarefree numbers?", + "statement": "Let $f\\in \\mathbb{Z}[x]$ be an irreducible polynomial of degree $k>2$ (and suppose that $k\\neq 2^l$ for any $l\\geq 1$) such that the leading coefficient of $f$ is positive. Does the set of integers $n\\geq 1$ for which $f(n)$ is $(k-1)$-power-free have positive density? If $k>3$, and for all primes $p$ there exists $n$ such that $p^{k-2}\\nmid f(n)$, then are there infinitely many $n$ for which $f(n)$ is $(k-2)$-power-free? In particular, does\\[n^4+2\\]represent infinitely many squarefree numbers?", "tags": [ "number theory" ], - "last_edited": "05 March 2026", + "last_edited": "31 March 2026", "latex_path": "/latex/978", "formalized": true, "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/978.lean", "oeis_urls": [], "comments_problem_id": 978, - "comments_count": 8 + "comments_count": 16 }, { "problem_id": 979, @@ -22203,7 +22213,7 @@ "https://oeis.org/A219429" ], "comments_problem_id": 985, - "comments_count": 1 + "comments_count": 2 }, { "problem_id": 986, @@ -22368,7 +22378,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 993, - "comments_count": 1 + "comments_count": 2 }, { "problem_id": 994, @@ -22435,8 +22445,8 @@ { "problem_id": 997, "problem_url": "/997", - "status_bucket": "open", - "status_dom_id": "open", + "status_bucket": "closed", + "status_dom_id": "solved", "status_label": "OPEN", "status_detail": "This is open, and cannot be resolved with a finite computation.", "prize_amount": "", @@ -22446,13 +22456,13 @@ "discrepancy", "primes" ], - "last_edited": "", + "last_edited": "01 April 2026", "latex_path": "/latex/997", "formalized": true, "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/997.lean", "oeis_urls": [], "comments_problem_id": 997, - "comments_count": 0 + "comments_count": 2 }, { "problem_id": 998, @@ -22723,7 +22733,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 1010, - "comments_count": 0 + "comments_count": 1 }, { "problem_id": 1011, @@ -23131,12 +23141,12 @@ "status_label": "OPEN", "status_detail": "This is open, and cannot be resolved with a finite computation.", "prize_amount": "", - "statement": "If $R(k,l)$ is the Ramsey number then prove the existence of some $c>0$ such that\\[\\lim_k \\frac{R(k+1,k)}{R(k,k)}> 1+c.\\]", + "statement": "Let $R(k,l)$ be the usual Ramsey number: the smallest $n$ such that if the edges of $K_n$ are coloured red and blue then there exists either a red $K_k$ or a blue $K_l$. Prove the existence of some $c>0$ such that\\[\\lim_{k\\to \\infty}\\frac{R(k+1,k)}{R(k,k)}> 1+c.\\]", "tags": [ "graph theory", "ramsey theory" ], - "last_edited": "03 December 2025", + "last_edited": "23 March 2026", "latex_path": "/latex/1030", "formalized": false, "formalized_url": "", @@ -23145,7 +23155,7 @@ "https://oeis.org/A059442" ], "comments_problem_id": 1030, - "comments_count": 1 + "comments_count": 2 }, { "problem_id": 1031, @@ -23306,7 +23316,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/1038.lean", "oeis_urls": [], "comments_problem_id": 1038, - "comments_count": 127 + "comments_count": 134 }, { "problem_id": 1039, @@ -23327,7 +23337,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 1039, - "comments_count": 1 + "comments_count": 9 }, { "problem_id": 1040, @@ -23347,7 +23357,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 1040, - "comments_count": 0 + "comments_count": 1 }, { "problem_id": 1041, @@ -23368,7 +23378,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/1041.lean", "oeis_urls": [], "comments_problem_id": 1041, - "comments_count": 2 + "comments_count": 41 }, { "problem_id": 1042, @@ -23435,8 +23445,8 @@ "problem_url": "/1045", "status_bucket": "open", "status_dom_id": "open", - "status_label": "FALSIFIABLE", - "status_detail": "Open, but could be disproved with a finite counterexample.", + "status_label": "OPEN", + "status_detail": "This is open, and cannot be resolved with a finite computation.", "prize_amount": "", "statement": "Let $z_1,\\ldots,z_n\\in \\mathbb{C}$ with $\\lvert z_i-z_j\\rvert\\leq 2$ for all $i,j$, and\\[\\Delta(z_1,\\ldots,z_n)=\\prod_{i\\neq j}\\lvert z_i-z_j\\rvert.\\]What is the maximum possible value of $\\Delta$? Is it maximised by taking the $z_i$ to be the vertices of a regular polygon?", "tags": [ @@ -23448,7 +23458,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 1045, - "comments_count": 43 + "comments_count": 45 }, { "problem_id": 1046, @@ -23528,7 +23538,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/1049.lean", "oeis_urls": [], "comments_problem_id": 1049, - "comments_count": 1 + "comments_count": 0 }, { "problem_id": 1050, @@ -24074,7 +24084,7 @@ "https://oeis.org/A064164" ], "comments_problem_id": 1074, - "comments_count": 3 + "comments_count": 5 }, { "problem_id": 1075, @@ -24516,7 +24526,7 @@ "https://oeis.org/A003458" ], "comments_problem_id": 1095, - "comments_count": 6 + "comments_count": 8 }, { "problem_id": 1096, @@ -24557,7 +24567,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/1097.lean", "oeis_urls": [], "comments_problem_id": 1097, - "comments_count": 11 + "comments_count": 17 }, { "problem_id": 1098, @@ -24683,7 +24693,7 @@ "https://oeis.org/A392164" ], "comments_problem_id": 1103, - "comments_count": 4 + "comments_count": 5 }, { "problem_id": 1104, @@ -24841,7 +24851,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 1110, - "comments_count": 3 + "comments_count": 4 }, { "problem_id": 1111, @@ -25066,7 +25076,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 1121, - "comments_count": 0 + "comments_count": 2 }, { "problem_id": 1122, @@ -25086,7 +25096,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 1122, - "comments_count": 0 + "comments_count": 1 }, { "problem_id": 1123, @@ -25100,7 +25110,7 @@ "tags": [ "algebra" ], - "last_edited": "31 December 2025", + "last_edited": "05 March 2026", "latex_path": "/latex/1123", "formalized": false, "formalized_url": "", @@ -25294,7 +25304,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 1132, - "comments_count": 1 + "comments_count": 2 }, { "problem_id": 1133, @@ -25490,7 +25500,7 @@ "https://oeis.org/A214583" ], "comments_problem_id": 1141, - "comments_count": 5 + "comments_count": 6 }, { "problem_id": 1142, @@ -25505,7 +25515,7 @@ "number theory", "primes" ], - "last_edited": "23 January 2026", + "last_edited": "05 March 2026", "latex_path": "/latex/1142", "formalized": true, "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/1142.lean", @@ -25513,7 +25523,7 @@ "https://oeis.org/A039669" ], "comments_problem_id": 1142, - "comments_count": 3 + "comments_count": 4 }, { "problem_id": 1143, @@ -25622,16 +25632,16 @@ { "problem_id": 1148, "problem_url": "/1148", - "status_bucket": "open", - "status_dom_id": "open", - "status_label": "OPEN", - "status_detail": "This is open, and cannot be resolved with a finite computation.", + "status_bucket": "closed", + "status_dom_id": "solved", + "status_label": "PROVED (LEAN)", + "status_detail": "This has been solved in the affirmative and the proof verified in Lean.", "prize_amount": "", "statement": "Can every large integer $n$ be written as $n=x^2+y^2-z^2$ with $\\max(x^2,y^2,z^2)\\leq n$?", "tags": [ "number theory" ], - "last_edited": "26 January 2026", + "last_edited": "23 March 2026", "latex_path": "/latex/1148", "formalized": true, "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/1148.lean", @@ -25640,7 +25650,7 @@ "https://oeis.org/A393168" ], "comments_problem_id": 1148, - "comments_count": 6 + "comments_count": 26 }, { "problem_id": 1149, @@ -25744,7 +25754,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 1153, - "comments_count": 7 + "comments_count": 10 }, { "problem_id": 1154, @@ -26163,8 +26173,8 @@ "problem_url": "/1174", "status_bucket": "open", "status_dom_id": "open", - "status_label": "OPEN", - "status_detail": "This is open, and cannot be resolved with a finite computation.", + "status_label": "NOT DISPROVABLE", + "status_detail": "Open in general, but there exist models of set theory where the result is true.", "prize_amount": "", "statement": "Does there exist a graph $G$ with no $K_4$ such that every edge colouring of $G$ with countably many colours contains a monochromatic $K_3$? Does there exist a graph $G$ with no $K_{\\aleph_1}$ such that every edge colouring of $G$ with countably many colours contains a monochromatic $K_{\\aleph_0}$?", "tags": [ @@ -26177,7 +26187,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 1174, - "comments_count": 1 + "comments_count": 2 }, { "problem_id": 1175, @@ -26205,8 +26215,8 @@ "problem_url": "/1176", "status_bucket": "open", "status_dom_id": "open", - "status_label": "OPEN", - "status_detail": "This is open, and cannot be resolved with a finite computation.", + "status_label": "NOT DISPROVABLE", + "status_detail": "Open in general, but there exist models of set theory where the result is true.", "prize_amount": "", "statement": "Let $G$ be a graph with chromatic number $\\aleph_1$. Is it true that there is a colouring of the edges with $\\aleph_1$ many colours such that, in any countable colouring of the vertices, there exists a vertex colour containing all edge colours?", "tags": [ @@ -26219,7 +26229,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/1176.lean", "oeis_urls": [], "comments_problem_id": 1176, - "comments_count": 0 + "comments_count": 1 }, { "problem_id": 1177, @@ -26284,6 +26294,88 @@ "oeis_urls": [], "comments_problem_id": 1179, "comments_count": 0 + }, + { + "problem_id": 1180, + "problem_url": "/1180", + "status_bucket": "closed", + "status_dom_id": "solved", + "status_label": "PROVED", + "status_detail": "This has been solved in the affirmative.", + "prize_amount": "", + "statement": "Let $\\epsilon>0$. Does there exist a constant $C_\\epsilon$ such that, for all primes $p$, every residue modulo $p$ is the sum of at most $C_\\epsilon$ many elements of\\[\\{ n^{-1} : 1\\leq n\\leq p^\\epsilon\\}\\]where $n^{-1}$ denotes the inverse of $n$ modulo $p$?", + "tags": [ + "number theory" + ], + "last_edited": "06 March 2026", + "latex_path": "/latex/1180", + "formalized": false, + "formalized_url": "", + "oeis_urls": [], + "comments_problem_id": 1180, + "comments_count": 0 + }, + { + "problem_id": 1181, + "problem_url": "/1181", + "status_bucket": "open", + "status_dom_id": "open", + "status_label": "OPEN", + "status_detail": "This is open, and cannot be resolved with a finite computation.", + "prize_amount": "", + "statement": "Let $q(n,k)$ denote the least prime which does not divide $\\prod_{1\\leq i\\leq k}(n+i)$. Is it true that there exists some $c>0$ such that, for all large $n$,\\[q(n,\\log n)<(1-c)(\\log n)^2?\\]", + "tags": [ + "number theory" + ], + "last_edited": "07 March 2026", + "latex_path": "/latex/1181", + "formalized": false, + "formalized_url": "", + "oeis_urls": [], + "comments_problem_id": 1181, + "comments_count": 0 + }, + { + "problem_id": 1182, + "problem_url": "/1182", + "status_bucket": "open", + "status_dom_id": "open", + "status_label": "OPEN", + "status_detail": "This is open, and cannot be resolved with a finite computation.", + "prize_amount": "", + "statement": "Let $f(n)$ be maximal such that there is a connected graph $G$ with $n$ vertices and $f(n)$ edges such that\\[R(K_3,G)= 2n-1.\\]Let $F(n)$ be maximal such that every connected graph $G$ with $n$ vertices and $\\leq F(n)$ edges has\\[R(K_3,G)= 2n-1.\\]Estimate $f(n)$ and $F(n)$. In particular, is it true that $F(n)/n\\to \\infty$?", + "tags": [ + "graph theory", + "ramsey theory" + ], + "last_edited": "", + "latex_path": "/latex/1182", + "formalized": false, + "formalized_url": "", + "oeis_urls": [], + "comments_problem_id": 1182, + "comments_count": 3 + }, + { + "problem_id": 1183, + "problem_url": "/1183", + "status_bucket": "open", + "status_dom_id": "open", + "status_label": "OPEN", + "status_detail": "This is open, and cannot be resolved with a finite computation.", + "prize_amount": "", + "statement": "Let $f(n)$ be maximal such that in any $2$-colouring of the subsets of $\\{1,\\ldots,n\\}$ there is always a monochromatic family of at least $f(n)$ sets which is closed under taking unions and intersections. Estimate $f(n)$. Let $F(n)$ be defined similarly, except that we only require the family be closed under taking unions. Estimate $F(n)$. In particular, is it true that $F(n)\\geq n^{\\omega(n)}$ for some $\\omega(n)\\to \\infty$ as $n\\to \\infty$, and $F(n)<(1+o(1))^n$?", + "tags": [ + "combinatorics", + "ramsey theory" + ], + "last_edited": "", + "latex_path": "/latex/1183", + "formalized": false, + "formalized_url": "", + "oeis_urls": [], + "comments_problem_id": 1183, + "comments_count": 10 } ] } diff --git a/packs/erdos-open-problems/data/erdos_problems.closed.json b/packs/erdos-open-problems/data/erdos_problems.closed.json index 310d4b8..98449d4 100644 --- a/packs/erdos-open-problems/data/erdos_problems.closed.json +++ b/packs/erdos-open-problems/data/erdos_problems.closed.json @@ -2,32 +2,33 @@ "schema_version": "1.0.0", "subset": "closed", "active_status": "open", - "generated_at_utc": "2026-03-05T15:52:31Z", + "generated_at_utc": "2026-04-01T06:51:20Z", "source": { "site": "erdosproblems.com", "url": "https://erdosproblems.com/range/1-end", - "source_sha256": "72366d21b9530355396bef95b3ead90176a9c634b7ecd68fd30c85bad703a0c1", + "source_sha256": "870c67de08d4d2a7667ad4a3cd9b930d3a9809cca047a50fa20ab5b2b22fc23d", "solve_count": { - "raw": "488 solved out of 1179 shown", - "solved": 488, - "shown": 1179 + "raw": "495 solved out of 1183 shown", + "solved": 495, + "shown": 1183 } }, "summary": { - "total": 488, + "total": 495, "open": 0, - "closed": 488, + "closed": 495, "unknown": 0, "status_label_counts": { "DECIDABLE": 7, - "DISPROVED": 76, - "DISPROVED (LEAN)": 39, + "DISPROVED": 75, + "DISPROVED (LEAN)": 42, "INDEPENDENT": 3, "NOT PROVABLE": 1, - "PROVED": 237, - "PROVED (LEAN)": 63, - "SOLVED": 52, - "SOLVED (LEAN)": 10 + "OPEN": 1, + "PROVED": 235, + "PROVED (LEAN)": 69, + "SOLVED": 51, + "SOLVED (LEAN)": 11 } }, "problem_ids": [ @@ -81,6 +82,7 @@ 116, 118, 121, + 125, 127, 133, 134, @@ -222,6 +224,7 @@ 448, 449, 453, + 457, 459, 464, 465, @@ -305,6 +308,7 @@ 646, 648, 649, + 650, 651, 652, 656, @@ -402,6 +406,7 @@ 877, 880, 882, + 884, 894, 895, 897, @@ -445,6 +450,7 @@ 991, 992, 994, + 997, 998, 999, 1000, @@ -513,12 +519,14 @@ 1136, 1140, 1147, + 1148, 1149, 1161, 1164, 1165, 1166, - 1179 + 1179, + 1180 ], "problems": [ { @@ -670,7 +678,7 @@ "graph theory", "chromatic number" ], - "last_edited": "23 January 2026", + "last_edited": "07 March 2026", "latex_path": "/latex/19", "formalized": false, "formalized_url": "", @@ -1611,6 +1619,29 @@ "comments_problem_id": 121, "comments_count": 0 }, + { + "problem_id": 125, + "problem_url": "/125", + "status_bucket": "closed", + "status_dom_id": "solved", + "status_label": "DISPROVED (LEAN)", + "status_detail": "This has been solved in the negative and the proof verified in Lean.", + "prize_amount": "", + "statement": "Let $A = \\{ \\sum\\epsilon_k3^k : \\epsilon_k\\in \\{0,1\\}\\}$ be the set of integers which have only the digits $0,1$ when written base $3$, and $B=\\{ \\sum\\epsilon_k4^k : \\epsilon_k\\in \\{0,1\\}\\}$ be the set of integers which have only the digits $0,1$ when written base $4$. Does $A+B$ have positive lower density?", + "tags": [ + "number theory", + "base representations" + ], + "last_edited": "30 March 2026", + "latex_path": "/latex/125", + "formalized": true, + "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/125.lean", + "oeis_urls": [ + "https://oeis.org/A367090" + ], + "comments_problem_id": 125, + "comments_count": 21 + }, { "problem_id": 127, "problem_url": "/127", @@ -1810,8 +1841,8 @@ "problem_url": "/150", "status_bucket": "closed", "status_dom_id": "solved", - "status_label": "PROVED", - "status_detail": "This has been solved in the affirmative.", + "status_label": "PROVED (LEAN)", + "status_detail": "This has been solved in the affirmative and the proof verified in Lean.", "prize_amount": "", "statement": "A minimal cut of a graph is a minimal set of vertices whose removal disconnects the graph. Let $c(n)$ be the maximum number of minimal cuts a graph on $n$ vertices can have. Does $c(n)^{1/n}\\to \\alpha$ for some $\\alpha <2$?", "tags": [ @@ -1823,7 +1854,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 150, - "comments_count": 0 + "comments_count": 1 }, { "problem_id": 154, @@ -2024,12 +2055,12 @@ "status_dom_id": "solved", "status_label": "PROVED", "status_detail": "This has been solved in the affirmative.", - "prize_amount": "", + "prize_amount": "$100", "statement": "Let $k\\geq 3$. What is the maximum number of edges that a graph on $n$ vertices can contain if it does not have a $k$-regular subgraph? Is it $\\ll n^{1+o(1)}$?", "tags": [ "graph theory" ], - "last_edited": "23 January 2026", + "last_edited": "07 March 2026", "latex_path": "/latex/182", "formalized": false, "formalized_url": "", @@ -2211,8 +2242,8 @@ "problem_url": "/204", "status_bucket": "closed", "status_dom_id": "solved", - "status_label": "DISPROVED", - "status_detail": "This has been solved in the negative.", + "status_label": "DISPROVED (LEAN)", + "status_detail": "This has been solved in the negative and the proof verified in Lean.", "prize_amount": "", "statement": "Are there $n$ such that there is a covering system with moduli the divisors of $n$ which is 'as disjoint as possible'? That is, for all $d\\mid n$ with $d>1$ there is an associated $a_d$ such that every integer is congruent to some $a_d\\pmod{d}$, and if there is some integer $x$ with\\[x\\equiv a_d\\pmod{d}\\textrm{ and }x\\equiv a_{d'}\\pmod{d'}\\]then $(d,d')=1$.", "tags": [ @@ -2225,7 +2256,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/204.lean", "oeis_urls": [], "comments_problem_id": 204, - "comments_count": 0 + "comments_count": 1 }, { "problem_id": 205, @@ -2483,7 +2514,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 221, - "comments_count": 2 + "comments_count": 4 }, { "problem_id": 223, @@ -2538,7 +2569,7 @@ "tags": [ "analysis" ], - "last_edited": "01 February 2026", + "last_edited": "05 March 2026", "latex_path": "/latex/225", "formalized": false, "formalized_url": "", @@ -3270,7 +3301,7 @@ "number theory", "unit fractions" ], - "last_edited": "23 January 2026", + "last_edited": "31 March 2026", "latex_path": "/latex/298", "formalized": true, "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/298.lean", @@ -3448,7 +3479,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 314, - "comments_count": 1 + "comments_count": 3 }, { "problem_id": 315, @@ -3724,7 +3755,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/355.lean", "oeis_urls": [], "comments_problem_id": 355, - "comments_count": 16 + "comments_count": 18 }, { "problem_id": 356, @@ -3791,8 +3822,8 @@ "problem_url": "/363", "status_bucket": "closed", "status_dom_id": "solved", - "status_label": "DISPROVED", - "status_detail": "This has been solved in the negative.", + "status_label": "DISPROVED (LEAN)", + "status_detail": "This has been solved in the negative and the proof verified in Lean.", "prize_amount": "", "statement": "Is it true that there are only finitely many collections of disjoint intervals $I_1,\\ldots,I_n$ of size $\\lvert I_i\\rvert \\geq 4$ for $1\\leq i\\leq n$ such that\\[\\prod_{1\\leq i\\leq n}\\prod_{m\\in I_i}m\\]is a square?", "tags": [ @@ -3804,7 +3835,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 363, - "comments_count": 1 + "comments_count": 2 }, { "problem_id": 370, @@ -4584,13 +4615,35 @@ "comments_problem_id": 453, "comments_count": 1 }, + { + "problem_id": 457, + "problem_url": "/457", + "status_bucket": "closed", + "status_dom_id": "solved", + "status_label": "PROVED (LEAN)", + "status_detail": "This has been solved in the affirmative and the proof verified in Lean.", + "prize_amount": "", + "statement": "Is there some $\\epsilon>0$ such that there are infinitely many $n$ where all primes $p\\leq (2+\\epsilon)\\log n$ divide\\[\\prod_{1\\leq i\\leq \\log n}(n+i)?\\]", + "tags": [ + "number theory" + ], + "last_edited": "07 March 2026", + "latex_path": "/latex/457", + "formalized": true, + "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/457.lean", + "oeis_urls": [ + "https://oeis.org/A391668" + ], + "comments_problem_id": 457, + "comments_count": 10 + }, { "problem_id": 459, "problem_url": "/459", "status_bucket": "closed", "status_dom_id": "solved", - "status_label": "SOLVED", - "status_detail": "This has been resolved in some other way than a proof or disproof.", + "status_label": "SOLVED (LEAN)", + "status_detail": "This has been resolved in some other way than a proof or disproof, and that resolution verified in Lean.", "prize_amount": "", "statement": "Let $f(u)$ be the largest $v$ such that no $m\\in (u,v)$ is composed entirely of primes dividing $uv$. Estimate $f(u)$.", "tags": [ @@ -4605,7 +4658,7 @@ "https://oeis.org/A289280" ], "comments_problem_id": 459, - "comments_count": 2 + "comments_count": 3 }, { "problem_id": 464, @@ -4954,7 +5007,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/494.lean", "oeis_urls": [], "comments_problem_id": 494, - "comments_count": 2 + "comments_count": 3 }, { "problem_id": 496, @@ -5427,7 +5480,7 @@ "tags": [ "number theory" ], - "last_edited": "28 December 2025", + "last_edited": "06 March 2026", "latex_path": "/latex/540", "formalized": false, "formalized_url": "", @@ -6313,6 +6366,28 @@ "comments_problem_id": 649, "comments_count": 2 }, + { + "problem_id": 650, + "problem_url": "/650", + "status_bucket": "closed", + "status_dom_id": "solved", + "status_label": "PROVED (LEAN)", + "status_detail": "This has been solved in the affirmative and the proof verified in Lean.", + "prize_amount": "", + "statement": "Let $f(m)$ be such that if $A\\subseteq \\{1,\\ldots,N\\}$ has $\\lvert A\\rvert=m$ then every interval in $[1,\\infty)$ of length $2N$ contains $\\geq f(m)$ many distinct integers $b_1,\\ldots,b_r$ where each $b_i$ is divisible by some $a_i\\in A$, where $a_1,\\ldots,a_r$ are distinct. Estimate $f(m)$. In particular is it true that $f(m)\\leq \\sqrt{m}$?", + "tags": [ + "number theory" + ], + "last_edited": "01 April 2026", + "latex_path": "/latex/650", + "formalized": false, + "formalized_url": "", + "oeis_urls": [ + "https://oeis.org/A027434" + ], + "comments_problem_id": 650, + "comments_count": 28 + }, { "problem_id": 651, "problem_url": "/651", @@ -6782,7 +6857,7 @@ "graph theory", "ramsey theory" ], - "last_edited": "26 October 2025", + "last_edited": "07 March 2026", "latex_path": "/latex/720", "formalized": false, "formalized_url": "", @@ -6832,7 +6907,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 722, - "comments_count": 0 + "comments_count": 1 }, { "problem_id": 728, @@ -6853,7 +6928,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/728.lean", "oeis_urls": [], "comments_problem_id": 728, - "comments_count": 84 + "comments_count": 86 }, { "problem_id": 729, @@ -7191,8 +7266,8 @@ "problem_url": "/756", "status_bucket": "closed", "status_dom_id": "solved", - "status_label": "PROVED", - "status_detail": "This has been solved in the affirmative.", + "status_label": "PROVED (LEAN)", + "status_detail": "This has been solved in the affirmative and the proof verified in Lean.", "prize_amount": "", "statement": "Let $A\\subset \\mathbb{R}^2$ be a set of $n$ points. Can there be $\\gg n$ many distinct distances each of which occurs for more than $n$ many pairs from $A$?", "tags": [ @@ -7205,7 +7280,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 756, - "comments_count": 0 + "comments_count": 1 }, { "problem_id": 758, @@ -7528,20 +7603,20 @@ "problem_url": "/785", "status_bucket": "closed", "status_dom_id": "solved", - "status_label": "PROVED", - "status_detail": "This has been solved in the affirmative.", + "status_label": "PROVED (LEAN)", + "status_detail": "This has been solved in the affirmative and the proof verified in Lean.", "prize_amount": "", "statement": "Let $A,B\\subseteq \\mathbb{N}$ be infinite sets such that $A+B$ contains all large integers. Let $A(x)=\\lvert A\\cap [1,x]\\rvert$ and similarly for $B(x)$. Is it true that if $A(x)B(x)\\sim x$ then\\[A(x)B(x)-x\\to \\infty\\]as $x\\to \\infty$?", "tags": [ "additive combinatorics" ], - "last_edited": "", + "last_edited": "07 March 2026", "latex_path": "/latex/785", "formalized": false, "formalized_url": "", "oeis_urls": [], "comments_problem_id": 785, - "comments_count": 2 + "comments_count": 5 }, { "problem_id": 794, @@ -8145,7 +8220,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/848.lean", "oeis_urls": [], "comments_problem_id": 848, - "comments_count": 18 + "comments_count": 47 }, { "problem_id": 861, @@ -8341,6 +8416,27 @@ "comments_problem_id": 882, "comments_count": 0 }, + { + "problem_id": 884, + "problem_url": "/884", + "status_bucket": "closed", + "status_dom_id": "solved", + "status_label": "DISPROVED", + "status_detail": "This has been solved in the negative.", + "prize_amount": "", + "statement": "Is it true that, for any $n$, if $d_1<\\cdots 0$, if $k$ is sufficiently large then, for all $n>0$ and intervals $I\\subseteq [0,1]$,\\[\\lvert \\# \\{ n0$. Does there exist a constant $C_\\epsilon$ such that, for all primes $p$, every residue modulo $p$ is the sum of at most $C_\\epsilon$ many elements of\\[\\{ n^{-1} : 1\\leq n\\leq p^\\epsilon\\}\\]where $n^{-1}$ denotes the inverse of $n$ modulo $p$?", + "tags": [ + "number theory" + ], + "last_edited": "06 March 2026", + "latex_path": "/latex/1180", + "formalized": false, + "formalized_url": "", + "oeis_urls": [], + "comments_problem_id": 1180, + "comments_count": 0 } ] } diff --git a/packs/erdos-open-problems/data/erdos_problems.open.json b/packs/erdos-open-problems/data/erdos_problems.open.json index ba08458..b9cc68d 100644 --- a/packs/erdos-open-problems/data/erdos_problems.open.json +++ b/packs/erdos-open-problems/data/erdos_problems.open.json @@ -2,30 +2,32 @@ "schema_version": "1.0.0", "subset": "open", "active_status": "open", - "generated_at_utc": "2026-03-05T15:52:31Z", + "generated_at_utc": "2026-04-01T06:51:20Z", "source": { "site": "erdosproblems.com", "url": "https://erdosproblems.com/range/1-end", - "source_sha256": "72366d21b9530355396bef95b3ead90176a9c634b7ecd68fd30c85bad703a0c1", + "source_sha256": "870c67de08d4d2a7667ad4a3cd9b930d3a9809cca047a50fa20ab5b2b22fc23d", "solve_count": { - "raw": "488 solved out of 1179 shown", - "solved": 488, - "shown": 1179 + "raw": "495 solved out of 1183 shown", + "solved": 495, + "shown": 1183 } }, "summary": { - "total": 691, - "open": 691, + "total": 688, + "open": 688, "closed": 0, "unknown": 0, "status_label_counts": { "DECIDABLE": 2, + "DISPROVED": 1, "DISPROVED (LEAN)": 1, - "FALSIFIABLE": 29, - "NOT DISPROVABLE": 2, + "FALSIFIABLE": 27, + "NOT DISPROVABLE": 4, "NOT PROVABLE": 3, - "OPEN": 645, - "PROVED": 2, + "OPEN": 639, + "PROVED": 3, + "PROVED (LEAN)": 1, "VERIFIABLE": 7 } }, @@ -104,7 +106,6 @@ 122, 123, 124, - 125, 126, 128, 129, @@ -295,7 +296,6 @@ 454, 455, 456, - 457, 458, 460, 461, @@ -405,7 +405,6 @@ 643, 644, 647, - 650, 653, 654, 655, @@ -542,7 +541,6 @@ 879, 881, 883, - 884, 885, 886, 887, @@ -612,7 +610,6 @@ 993, 995, 996, - 997, 1002, 1003, 1004, @@ -695,7 +692,6 @@ 1144, 1145, 1146, - 1148, 1150, 1151, 1152, @@ -720,7 +716,10 @@ 1175, 1176, 1177, - 1178 + 1178, + 1181, + 1182, + 1183 ], "problems": [ { @@ -870,8 +869,8 @@ "problem_url": "/11", "status_bucket": "open", "status_dom_id": "open", - "status_label": "FALSIFIABLE", - "status_detail": "Open, but could be disproved with a finite counterexample.", + "status_label": "OPEN", + "status_detail": "This is open, and cannot be resolved with a finite computation.", "prize_amount": "", "statement": "Is every large odd integer $n$ the sum of a squarefree number and a power of 2?", "tags": [ @@ -993,8 +992,8 @@ ], "last_edited": "20 January 2026", "latex_path": "/latex/18", - "formalized": false, - "formalized_url": "", + "formalized": true, + "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/18.lean", "oeis_urls": [ "https://oeis.org/A005153" ], @@ -1013,7 +1012,7 @@ "tags": [ "combinatorics" ], - "last_edited": "25 January 2026", + "last_edited": "07 March 2026", "latex_path": "/latex/20", "formalized": true, "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/20.lean", @@ -1063,7 +1062,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/25.lean", "oeis_urls": [], "comments_problem_id": 25, - "comments_count": 2 + "comments_count": 7 }, { "problem_id": 28, @@ -1152,7 +1151,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/33.lean", "oeis_urls": [], "comments_problem_id": 33, - "comments_count": 4 + "comments_count": 5 }, { "problem_id": 36, @@ -1346,8 +1345,8 @@ ], "last_edited": "", "latex_path": "/latex/50", - "formalized": false, - "formalized_url": "", + "formalized": true, + "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/50.lean", "oeis_urls": [], "comments_problem_id": 50, "comments_count": 0 @@ -1388,7 +1387,7 @@ "number theory", "additive combinatorics" ], - "last_edited": "23 January 2026", + "last_edited": "23 March 2026", "latex_path": "/latex/52", "formalized": false, "formalized_url": "", @@ -1747,8 +1746,8 @@ "problem_url": "/85", "status_bucket": "open", "status_dom_id": "open", - "status_label": "FALSIFIABLE", - "status_detail": "Open, but could be disproved with a finite counterexample.", + "status_label": "OPEN", + "status_detail": "This is open, and cannot be resolved with a finite computation.", "prize_amount": "", "statement": "Let $n\\geq 4$ and $f(n)$ be minimal such that every graph on $n$ vertices with minimal degree $\\geq f(n)$ contains a $C_4$. Is it true that, for all large $n$, $f(n+1)\\geq f(n)$?", "tags": [ @@ -1878,7 +1877,7 @@ "https://oeis.org/A186704" ], "comments_problem_id": 91, - "comments_count": 5 + "comments_count": 6 }, { "problem_id": 92, @@ -2105,7 +2104,7 @@ "tags": [ "geometry" ], - "last_edited": "", + "last_edited": "06 March 2026", "latex_path": "/latex/106", "formalized": false, "formalized_url": "", @@ -2206,8 +2205,8 @@ "problem_url": "/114", "status_bucket": "open", "status_dom_id": "open", - "status_label": "OPEN", - "status_detail": "This is open, and cannot be resolved with a finite computation.", + "status_label": "FALSIFIABLE", + "status_detail": "Open, but could be disproved with a finite counterexample.", "prize_amount": "$250", "statement": "If $p(z)\\in\\mathbb{C}[z]$ is a monic polynomial of degree $n$ then is the length of the curve $\\{ z\\in \\mathbb{C} : \\lvert p(z)\\rvert=1\\}$ maximised when $p(z)=z^n-1$?", "tags": [ @@ -2220,7 +2219,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 114, - "comments_count": 3 + "comments_count": 4 }, { "problem_id": 117, @@ -2281,7 +2280,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/120.lean", "oeis_urls": [], "comments_problem_id": 120, - "comments_count": 1 + "comments_count": 3 }, { "problem_id": 122, @@ -2301,7 +2300,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 122, - "comments_count": 0 + "comments_count": 3 }, { "problem_id": 123, @@ -2345,29 +2344,6 @@ "comments_problem_id": 124, "comments_count": 13 }, - { - "problem_id": 125, - "problem_url": "/125", - "status_bucket": "open", - "status_dom_id": "open", - "status_label": "OPEN", - "status_detail": "This is open, and cannot be resolved with a finite computation.", - "prize_amount": "", - "statement": "Let $A = \\{ \\sum\\epsilon_k3^k : \\epsilon_k\\in \\{0,1\\}\\}$ be the set of integers which have only the digits $0,1$ when written base $3$, and $B=\\{ \\sum\\epsilon_k4^k : \\epsilon_k\\in \\{0,1\\}\\}$ be the set of integers which have only the digits $0,1$ when written base $4$. Does $A+B$ have positive density?", - "tags": [ - "number theory", - "base representations" - ], - "last_edited": "", - "latex_path": "/latex/125", - "formalized": true, - "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/125.lean", - "oeis_urls": [ - "https://oeis.org/A367090" - ], - "comments_problem_id": 125, - "comments_count": 13 - }, { "problem_id": 126, "problem_url": "/126", @@ -2826,13 +2802,13 @@ "status_dom_id": "open", "status_label": "OPEN", "status_detail": "This is open, and cannot be resolved with a finite computation.", - "prize_amount": "", + "prize_amount": "$100", "statement": "There exists some constant $c>0$ such that $$R(C_4,K_n) \\ll n^{2-c}.$$", "tags": [ "graph theory", "ramsey theory" ], - "last_edited": "", + "last_edited": "07 March 2026", "latex_path": "/latex/159", "formalized": false, "formalized_url": "", @@ -2919,7 +2895,7 @@ "graph theory", "ramsey theory" ], - "last_edited": "28 December 2025", + "last_edited": "07 March 2026", "latex_path": "/latex/165", "formalized": false, "formalized_url": "", @@ -2961,7 +2937,7 @@ "tags": [ "additive combinatorics" ], - "last_edited": "24 October 2025", + "last_edited": "23 March 2026", "latex_path": "/latex/168", "formalized": true, "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/168.lean", @@ -3102,7 +3078,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 176, - "comments_count": 1 + "comments_count": 3 }, { "problem_id": 177, @@ -3205,11 +3181,11 @@ ], "last_edited": "", "latex_path": "/latex/184", - "formalized": false, - "formalized_url": "", + "formalized": true, + "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/184.lean", "oeis_urls": [], "comments_problem_id": 184, - "comments_count": 0 + "comments_count": 1 }, { "problem_id": 187, @@ -3289,8 +3265,8 @@ ], "last_edited": "", "latex_path": "/latex/193", - "formalized": false, - "formalized_url": "", + "formalized": true, + "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/193.lean", "oeis_urls": [ "https://oeis.org/A231255" ], @@ -3693,7 +3669,7 @@ "https://oeis.org/A387704" ], "comments_problem_id": 241, - "comments_count": 2 + "comments_count": 3 }, { "problem_id": 242, @@ -3744,7 +3720,7 @@ "https://oeis.org/A000058" ], "comments_problem_id": 243, - "comments_count": 6 + "comments_count": 7 }, { "problem_id": 244, @@ -3872,8 +3848,8 @@ ], "last_edited": "07 December 2025", "latex_path": "/latex/254", - "formalized": false, - "formalized_url": "", + "formalized": true, + "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/254.lean", "oeis_urls": [], "comments_problem_id": 254, "comments_count": 3 @@ -3952,8 +3928,8 @@ ], "last_edited": "01 February 2026", "latex_path": "/latex/260", - "formalized": false, - "formalized_url": "", + "formalized": true, + "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/260.lean", "oeis_urls": [], "comments_problem_id": 260, "comments_count": 2 @@ -4162,7 +4138,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/274.lean", "oeis_urls": [], "comments_problem_id": 274, - "comments_count": 2 + "comments_count": 3 }, { "problem_id": 276, @@ -4270,7 +4246,7 @@ "https://oeis.org/A380791" ], "comments_problem_id": 283, - "comments_count": 2 + "comments_count": 3 }, { "problem_id": 287, @@ -4723,8 +4699,8 @@ ], "last_edited": "", "latex_path": "/latex/323", - "formalized": false, - "formalized_url": "", + "formalized": true, + "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/323.lean", "oeis_urls": [], "comments_problem_id": 323, "comments_count": 0 @@ -4769,7 +4745,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/325.lean", "oeis_urls": [], "comments_problem_id": 325, - "comments_count": 0 + "comments_count": 2 }, { "problem_id": 326, @@ -4790,7 +4766,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/326.lean", "oeis_urls": [], "comments_problem_id": 326, - "comments_count": 2 + "comments_count": 3 }, { "problem_id": 327, @@ -4849,7 +4825,7 @@ "number theory", "additive basis" ], - "last_edited": "08 December 2025", + "last_edited": "31 March 2026", "latex_path": "/latex/330", "formalized": true, "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/330.lean", @@ -4893,7 +4869,10 @@ "latex_path": "/latex/334", "formalized": false, "formalized_url": "", - "oeis_urls": [], + "oeis_urls": [ + "https://oeis.org/A045535", + "https://oeis.org/A062241" + ], "comments_problem_id": 334, "comments_count": 2 }, @@ -5019,13 +4998,13 @@ ], "last_edited": "30 September 2025", "latex_path": "/latex/342", - "formalized": false, - "formalized_url": "", + "formalized": true, + "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/342.lean", "oeis_urls": [ "https://oeis.org/A002858" ], "comments_problem_id": 342, - "comments_count": 11 + "comments_count": 18 }, { "problem_id": 345, @@ -5111,7 +5090,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/349.lean", "oeis_urls": [], "comments_problem_id": 349, - "comments_count": 8 + "comments_count": 12 }, { "problem_id": 351, @@ -5218,7 +5197,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/358.lean", "oeis_urls": [], "comments_problem_id": 358, - "comments_count": 19 + "comments_count": 21 }, { "problem_id": 359, @@ -5309,7 +5288,7 @@ "https://oeis.org/A175155" ], "comments_problem_id": 365, - "comments_count": 2 + "comments_count": 3 }, { "problem_id": 366, @@ -5319,12 +5298,12 @@ "status_label": "VERIFIABLE", "status_detail": "Open, but could be proved with a finite example.", "prize_amount": "", - "statement": "Are there any 2-full $n$ such that $n+1$ is 3-full? That is, if $p\\mid n$ then $p^2\\mid n$ and if $p\\mid n+1$ then $p^3\\mid n+1$.", + "statement": "Are there any $2$-full $n$ such that $n+1$ is $3$-full? That is, if $p\\mid n$ then $p^2\\mid n$ and if $p\\mid n+1$ then $p^3\\mid n+1$.", "tags": [ "number theory", "powerful" ], - "last_edited": "20 December 2025", + "last_edited": "23 March 2026", "latex_path": "/latex/366", "formalized": true, "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/366.lean", @@ -5342,12 +5321,12 @@ "status_label": "OPEN", "status_detail": "This is open, and cannot be resolved with a finite computation.", "prize_amount": "", - "statement": "Let $B_2(n)$ be the 2-full part of $n$ (that is, $B_2(n)=n/n'$ where $n'$ is the product of all primes that divide $n$ exactly once). Is it true that, for every fixed $k\\geq 1$,\\[\\prod_{n\\leq m0$ and $k\\geq 2$. Is it true that, for all sufficiently large $n$, there is a sequence of $k$ consecutive integers in $\\{1,\\ldots,n\\}$ all of which are $n^\\epsilon$-smooth?", "tags": [ @@ -5397,7 +5376,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 369, - "comments_count": 0 + "comments_count": 11 }, { "problem_id": 371, @@ -5467,7 +5446,7 @@ "https://oeis.org/A389148" ], "comments_problem_id": 374, - "comments_count": 0 + "comments_count": 1 }, { "problem_id": 375, @@ -5540,8 +5519,8 @@ "problem_url": "/380", "status_bucket": "open", "status_dom_id": "open", - "status_label": "OPEN", - "status_detail": "This is open, and cannot be resolved with a finite computation.", + "status_label": "PROVED", + "status_detail": "This has been solved in the affirmative.", "prize_amount": "", "statement": "We call an interval $[u,v]$ 'bad' if the greatest prime factor of $\\prod_{u\\leq m\\leq v}m$ occurs with an exponent greater than $1$. Let $B(x)$ count the number of $n\\leq x$ which are contained in at least one bad interval. Is it true that\\[B(x)\\sim \\#\\{ n\\leq x: P(n)^2\\mid n\\},\\]where $P(n)$ is the largest prime factor of $n$?", "tags": [ @@ -5558,7 +5537,7 @@ "https://oeis.org/A389100" ], "comments_problem_id": 380, - "comments_count": 5 + "comments_count": 9 }, { "problem_id": 382, @@ -5645,7 +5624,7 @@ "https://oeis.org/A280992" ], "comments_problem_id": 386, - "comments_count": 12 + "comments_count": 13 }, { "problem_id": 387, @@ -5686,7 +5665,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 388, - "comments_count": 5 + "comments_count": 10 }, { "problem_id": 389, @@ -5708,7 +5687,7 @@ "https://oeis.org/A375071" ], "comments_problem_id": 389, - "comments_count": 6 + "comments_count": 8 }, { "problem_id": 390, @@ -5799,7 +5778,7 @@ "https://oeis.org/A375077" ], "comments_problem_id": 396, - "comments_count": 1 + "comments_count": 30 }, { "problem_id": 398, @@ -5814,15 +5793,16 @@ "number theory", "factorials" ], - "last_edited": "", + "last_edited": "01 April 2026", "latex_path": "/latex/398", "formalized": true, "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/398.lean", "oeis_urls": [ + "https://oeis.org/A141399", "https://oeis.org/A146968" ], "comments_problem_id": 398, - "comments_count": 6 + "comments_count": 9 }, { "problem_id": 400, @@ -5839,8 +5819,8 @@ ], "last_edited": "", "latex_path": "/latex/400", - "formalized": false, - "formalized_url": "", + "formalized": true, + "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/400.lean", "oeis_urls": [], "comments_problem_id": 400, "comments_count": 0 @@ -6192,7 +6172,7 @@ "tags": [ "number theory" ], - "last_edited": "16 January 2026", + "last_edited": "23 March 2026", "latex_path": "/latex/423", "formalized": false, "formalized_url": "", @@ -6200,7 +6180,7 @@ "https://oeis.org/A005243" ], "comments_problem_id": 423, - "comments_count": 18 + "comments_count": 38 }, { "problem_id": 424, @@ -6214,7 +6194,7 @@ "tags": [ "number theory" ], - "last_edited": "", + "last_edited": "31 March 2026", "latex_path": "/latex/424", "formalized": true, "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/424.lean", @@ -6363,8 +6343,8 @@ ], "last_edited": "27 December 2025", "latex_path": "/latex/445", - "formalized": false, - "formalized_url": "", + "formalized": true, + "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/445.lean", "oeis_urls": [], "comments_problem_id": 445, "comments_count": 1 @@ -6496,28 +6476,6 @@ "comments_problem_id": 456, "comments_count": 2 }, - { - "problem_id": 457, - "problem_url": "/457", - "status_bucket": "open", - "status_dom_id": "open", - "status_label": "OPEN", - "status_detail": "This is open, and cannot be resolved with a finite computation.", - "prize_amount": "", - "statement": "Is there some $\\epsilon>0$ such that there are infinitely many $n$ where all primes $p\\leq (2+\\epsilon)\\log n$ divide\\[\\prod_{1\\leq i\\leq \\log n}(n+i)?\\]", - "tags": [ - "number theory" - ], - "last_edited": "07 October 2025", - "latex_path": "/latex/457", - "formalized": true, - "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/457.lean", - "oeis_urls": [ - "https://oeis.org/A391668" - ], - "comments_problem_id": 457, - "comments_count": 7 - }, { "problem_id": 458, "problem_url": "/458", @@ -6775,7 +6733,7 @@ "number theory", "additive combinatorics" ], - "last_edited": "", + "last_edited": "05 March 2026", "latex_path": "/latex/475", "formalized": false, "formalized_url": "", @@ -6904,8 +6862,8 @@ "problem_url": "/488", "status_bucket": "open", "status_dom_id": "open", - "status_label": "OPEN", - "status_detail": "This is open, and cannot be resolved with a finite computation.", + "status_label": "FALSIFIABLE", + "status_detail": "Open, but could be disproved with a finite counterexample.", "prize_amount": "", "statement": "Let $A$ be a finite set and\\[B=\\{ n \\geq 1 : a\\mid n\\textrm{ for some }a\\in A\\}.\\]Is it true that, for every $m>n\\geq \\max(A)$,\\[\\frac{\\lvert B\\cap [1,m]\\rvert }{m}< 2\\frac{\\lvert B\\cap [1,n]\\rvert}{n}?\\]", "tags": [ @@ -6917,7 +6875,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/488.lean", "oeis_urls": [], "comments_problem_id": 488, - "comments_count": 14 + "comments_count": 27 }, { "problem_id": 489, @@ -7168,7 +7126,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/517.lean", "oeis_urls": [], "comments_problem_id": 517, - "comments_count": 0 + "comments_count": 1 }, { "problem_id": 520, @@ -7478,12 +7436,12 @@ "status_dom_id": "open", "status_label": "FALSIFIABLE", "status_detail": "Open, but could be disproved with a finite counterexample.", - "prize_amount": "", + "prize_amount": "$100", "statement": "Let $n\\geq k+1$. Every graph on $n$ vertices with at least $\\frac{k-1}{2}n+1$ edges contains every tree on $k+1$ vertices.", "tags": [ "graph theory" ], - "last_edited": "23 January 2026", + "last_edited": "07 March 2026", "latex_path": "/latex/548", "formalized": false, "formalized_url": "", @@ -7809,7 +7767,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 569, - "comments_count": 0 + "comments_count": 2 }, { "problem_id": 571, @@ -7824,7 +7782,7 @@ "graph theory", "turan number" ], - "last_edited": "18 January 2026", + "last_edited": "07 March 2026", "latex_path": "/latex/571", "formalized": false, "formalized_url": "", @@ -7882,8 +7840,8 @@ "problem_url": "/574", "status_bucket": "open", "status_dom_id": "open", - "status_label": "OPEN", - "status_detail": "This is open, and cannot be resolved with a finite computation.", + "status_label": "DISPROVED", + "status_detail": "This has been solved in the negative.", "prize_amount": "", "statement": "Is it true that, for $k\\geq 2$,\\[\\mathrm{ex}(n;\\{C_{2k-1},C_{2k}\\})=(1+o(1))(n/2)^{1+\\frac{1}{k}}.\\]", "tags": [ @@ -7896,7 +7854,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 574, - "comments_count": 0 + "comments_count": 1 }, { "problem_id": 575, @@ -7999,7 +7957,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 583, - "comments_count": 1 + "comments_count": 3 }, { "problem_id": 584, @@ -8211,7 +8169,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/598.lean", "oeis_urls": [], "comments_problem_id": 598, - "comments_count": 0 + "comments_count": 2 }, { "problem_id": 600, @@ -8309,7 +8267,7 @@ "geometry", "distances" ], - "last_edited": "15 October 2025", + "last_edited": "23 March 2026", "latex_path": "/latex/604", "formalized": false, "formalized_url": "", @@ -8456,7 +8414,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/617.lean", "oeis_urls": [], "comments_problem_id": 617, - "comments_count": 0 + "comments_count": 1 }, { "problem_id": 619, @@ -8662,7 +8620,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 633, - "comments_count": 2 + "comments_count": 5 }, { "problem_id": 634, @@ -8831,26 +8789,6 @@ "comments_problem_id": 647, "comments_count": 6 }, - { - "problem_id": 650, - "problem_url": "/650", - "status_bucket": "open", - "status_dom_id": "open", - "status_label": "OPEN", - "status_detail": "This is open, and cannot be resolved with a finite computation.", - "prize_amount": "", - "statement": "Let $f(m)$ be such that if $A\\subseteq \\{1,\\ldots,N\\}$ has $\\lvert A\\rvert=m$ then every interval in $[1,\\infty)$ of length $2N$ contains $\\geq f(m)$ many distinct integers $b_1,\\ldots,b_r$ where each $b_i$ is divisible by some $a_i\\in A$, where $a_1,\\ldots,a_r$ are distinct. Estimate $f(m)$. In particular is it true that $f(m)\\ll m^{1/2}$?", - "tags": [ - "number theory" - ], - "last_edited": "", - "latex_path": "/latex/650", - "formalized": false, - "formalized_url": "", - "oeis_urls": [], - "comments_problem_id": 650, - "comments_count": 0 - }, { "problem_id": 653, "problem_url": "/653", @@ -9228,7 +9166,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/677.lean", "oeis_urls": [], "comments_problem_id": 677, - "comments_count": 0 + "comments_count": 7 }, { "problem_id": 679, @@ -9310,8 +9248,8 @@ ], "last_edited": "31 December 2025", "latex_path": "/latex/683", - "formalized": false, - "formalized_url": "", + "formalized": true, + "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/683.lean", "oeis_urls": [ "https://oeis.org/A006530", "https://oeis.org/A074399", @@ -9334,7 +9272,7 @@ "primes", "binomial coefficients" ], - "last_edited": "23 January 2026", + "last_edited": "01 April 2026", "latex_path": "/latex/684", "formalized": false, "formalized_url": "", @@ -9384,7 +9322,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/686.lean", "oeis_urls": [], "comments_problem_id": 686, - "comments_count": 16 + "comments_count": 37 }, { "problem_id": 687, @@ -9660,7 +9598,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 704, - "comments_count": 1 + "comments_count": 4 }, { "problem_id": 706, @@ -9715,13 +9653,13 @@ "tags": [ "number theory" ], - "last_edited": "", + "last_edited": "23 March 2026", "latex_path": "/latex/709", "formalized": false, "formalized_url": "", "oeis_urls": [], "comments_problem_id": 709, - "comments_count": 0 + "comments_count": 2 }, { "problem_id": 710, @@ -9800,7 +9738,7 @@ "graph theory", "turan number" ], - "last_edited": "06 October 2025", + "last_edited": "07 March 2026", "latex_path": "/latex/713", "formalized": false, "formalized_url": "", @@ -10118,17 +10056,17 @@ "status_label": "OPEN", "status_detail": "This is open, and cannot be resolved with a finite computation.", "prize_amount": "", - "statement": "Let $A\\subseteq \\mathbb{N}$ be such that $A+A$ has positive density. Can one always decompose $A=A_1\\sqcup A_2$ such that $A_1+A_1$ and $A_2+A_2$ both have positive density? Is there a basis $A$ of order $2$ such that if $A=A_1\\sqcup A_2$ then $A_1+A_1$ and $A_2+A_2$ cannot both have bounded gaps?", + "statement": "Let $A\\subseteq \\mathbb{N}$ be such that $A+A$ has positive (upper) density. Can one always decompose $A=A_1\\sqcup A_2$ such that $A_1+A_1$ and $A_2+A_2$ both have positive (upper) density? Is there a basis $A$ of order $2$ such that if $A=A_1\\sqcup A_2$ then $A_1+A_1$ and $A_2+A_2$ cannot both have bounded gaps?", "tags": [ "additive combinatorics" ], - "last_edited": "", + "last_edited": "01 April 2026", "latex_path": "/latex/741", "formalized": true, "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/741.lean", "oeis_urls": [], "comments_problem_id": 741, - "comments_count": 0 + "comments_count": 3 }, { "problem_id": 743, @@ -10711,7 +10649,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 809, - "comments_count": 0 + "comments_count": 1 }, { "problem_id": 810, @@ -10770,8 +10708,8 @@ ], "last_edited": "", "latex_path": "/latex/812", - "formalized": false, - "formalized_url": "", + "formalized": true, + "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/812.lean", "oeis_urls": [], "comments_problem_id": 812, "comments_count": 0 @@ -11041,7 +10979,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/835.lean", "oeis_urls": [], "comments_problem_id": 835, - "comments_count": 4 + "comments_count": 5 }, { "problem_id": 836, @@ -11287,7 +11225,7 @@ "https://oeis.org/A390769" ], "comments_problem_id": 853, - "comments_count": 2 + "comments_count": 3 }, { "problem_id": 854, @@ -11317,8 +11255,8 @@ "problem_url": "/855", "status_bucket": "open", "status_dom_id": "open", - "status_label": "FALSIFIABLE", - "status_detail": "Open, but could be disproved with a finite counterexample.", + "status_label": "OPEN", + "status_detail": "This is open, and cannot be resolved with a finite computation.", "prize_amount": "", "statement": "If $\\pi(x)$ counts the number of primes in $[1,x]$ then is it true that (for large $x$ and $y$)\\[\\pi(x+y) \\leq \\pi(x)+\\pi(y)?\\]", "tags": [ @@ -11738,27 +11676,6 @@ "comments_problem_id": 883, "comments_count": 3 }, - { - "problem_id": 884, - "problem_url": "/884", - "status_bucket": "open", - "status_dom_id": "open", - "status_label": "OPEN", - "status_detail": "This is open, and cannot be resolved with a finite computation.", - "prize_amount": "", - "statement": "Is it true that, for any $n$, if $d_1<\\cdots 2$ (and suppose that $k\\neq 2^l$ for any $l\\geq 1$) such that the leading coefficient of $f$ is positive. Does the set of integers $n\\geq 1$ for which $f(n)$ is $(k-1)$-power-free have positive density? If $k>3$ then are there infinitely many $n$ for which $f(n)$ is $(k-2)$-power-free? In particular, does\\[n^4+2\\]represent infinitely many squarefree numbers?", + "statement": "Let $f\\in \\mathbb{Z}[x]$ be an irreducible polynomial of degree $k>2$ (and suppose that $k\\neq 2^l$ for any $l\\geq 1$) such that the leading coefficient of $f$ is positive. Does the set of integers $n\\geq 1$ for which $f(n)$ is $(k-1)$-power-free have positive density? If $k>3$, and for all primes $p$ there exists $n$ such that $p^{k-2}\\nmid f(n)$, then are there infinitely many $n$ for which $f(n)$ is $(k-2)$-power-free? In particular, does\\[n^4+2\\]represent infinitely many squarefree numbers?", "tags": [ "number theory" ], - "last_edited": "05 March 2026", + "last_edited": "31 March 2026", "latex_path": "/latex/978", "formalized": true, "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/978.lean", "oeis_urls": [], "comments_problem_id": 978, - "comments_count": 8 + "comments_count": 16 }, { "problem_id": 979, @@ -13098,7 +13015,7 @@ "https://oeis.org/A219429" ], "comments_problem_id": 985, - "comments_count": 1 + "comments_count": 2 }, { "problem_id": 986, @@ -13183,7 +13100,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 993, - "comments_count": 1 + "comments_count": 2 }, { "problem_id": 995, @@ -13226,28 +13143,6 @@ "comments_problem_id": 996, "comments_count": 0 }, - { - "problem_id": 997, - "problem_url": "/997", - "status_bucket": "open", - "status_dom_id": "open", - "status_label": "OPEN", - "status_detail": "This is open, and cannot be resolved with a finite computation.", - "prize_amount": "", - "statement": "Call $x_1,x_2,\\ldots \\in (0,1)$ well-distributed if, for every $\\epsilon>0$, if $k$ is sufficiently large then, for all $n>0$ and intervals $I\\subseteq [0,1]$,\\[\\lvert \\# \\{ n0$ such that\\[\\lim_k \\frac{R(k+1,k)}{R(k,k)}> 1+c.\\]", + "statement": "Let $R(k,l)$ be the usual Ramsey number: the smallest $n$ such that if the edges of $K_n$ are coloured red and blue then there exists either a red $K_k$ or a blue $K_l$. Prove the existence of some $c>0$ such that\\[\\lim_{k\\to \\infty}\\frac{R(k+1,k)}{R(k,k)}> 1+c.\\]", "tags": [ "graph theory", "ramsey theory" ], - "last_edited": "03 December 2025", + "last_edited": "23 March 2026", "latex_path": "/latex/1030", "formalized": false, "formalized_url": "", @@ -13504,7 +13399,7 @@ "https://oeis.org/A059442" ], "comments_problem_id": 1030, - "comments_count": 1 + "comments_count": 2 }, { "problem_id": 1032, @@ -13585,7 +13480,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/1038.lean", "oeis_urls": [], "comments_problem_id": 1038, - "comments_count": 127 + "comments_count": 134 }, { "problem_id": 1039, @@ -13606,7 +13501,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 1039, - "comments_count": 1 + "comments_count": 9 }, { "problem_id": 1040, @@ -13626,7 +13521,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 1040, - "comments_count": 0 + "comments_count": 1 }, { "problem_id": 1041, @@ -13647,15 +13542,15 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/1041.lean", "oeis_urls": [], "comments_problem_id": 1041, - "comments_count": 2 + "comments_count": 41 }, { "problem_id": 1045, "problem_url": "/1045", "status_bucket": "open", "status_dom_id": "open", - "status_label": "FALSIFIABLE", - "status_detail": "Open, but could be disproved with a finite counterexample.", + "status_label": "OPEN", + "status_detail": "This is open, and cannot be resolved with a finite computation.", "prize_amount": "", "statement": "Let $z_1,\\ldots,z_n\\in \\mathbb{C}$ with $\\lvert z_i-z_j\\rvert\\leq 2$ for all $i,j$, and\\[\\Delta(z_1,\\ldots,z_n)=\\prod_{i\\neq j}\\lvert z_i-z_j\\rvert.\\]What is the maximum possible value of $\\Delta$? Is it maximised by taking the $z_i$ to be the vertices of a regular polygon?", "tags": [ @@ -13667,7 +13562,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 1045, - "comments_count": 43 + "comments_count": 45 }, { "problem_id": 1049, @@ -13687,7 +13582,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/1049.lean", "oeis_urls": [], "comments_problem_id": 1049, - "comments_count": 1 + "comments_count": 0 }, { "problem_id": 1052, @@ -14087,7 +13982,7 @@ "https://oeis.org/A064164" ], "comments_problem_id": 1074, - "comments_count": 3 + "comments_count": 5 }, { "problem_id": 1075, @@ -14362,7 +14257,7 @@ "https://oeis.org/A003458" ], "comments_problem_id": 1095, - "comments_count": 6 + "comments_count": 8 }, { "problem_id": 1096, @@ -14403,7 +14298,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/1097.lean", "oeis_urls": [], "comments_problem_id": 1097, - "comments_count": 11 + "comments_count": 17 }, { "problem_id": 1100, @@ -14468,7 +14363,7 @@ "https://oeis.org/A392164" ], "comments_problem_id": 1103, - "comments_count": 4 + "comments_count": 5 }, { "problem_id": 1104, @@ -14605,7 +14500,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 1110, - "comments_count": 3 + "comments_count": 4 }, { "problem_id": 1111, @@ -14728,7 +14623,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 1122, - "comments_count": 0 + "comments_count": 1 }, { "problem_id": 1131, @@ -14770,7 +14665,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 1132, - "comments_count": 1 + "comments_count": 2 }, { "problem_id": 1133, @@ -14904,7 +14799,7 @@ "https://oeis.org/A214583" ], "comments_problem_id": 1141, - "comments_count": 5 + "comments_count": 6 }, { "problem_id": 1142, @@ -14919,7 +14814,7 @@ "number theory", "primes" ], - "last_edited": "23 January 2026", + "last_edited": "05 March 2026", "latex_path": "/latex/1142", "formalized": true, "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/1142.lean", @@ -14927,7 +14822,7 @@ "https://oeis.org/A039669" ], "comments_problem_id": 1142, - "comments_count": 3 + "comments_count": 4 }, { "problem_id": 1143, @@ -15012,29 +14907,6 @@ "comments_problem_id": 1146, "comments_count": 0 }, - { - "problem_id": 1148, - "problem_url": "/1148", - "status_bucket": "open", - "status_dom_id": "open", - "status_label": "OPEN", - "status_detail": "This is open, and cannot be resolved with a finite computation.", - "prize_amount": "", - "statement": "Can every large integer $n$ be written as $n=x^2+y^2-z^2$ with $\\max(x^2,y^2,z^2)\\leq n$?", - "tags": [ - "number theory" - ], - "last_edited": "26 January 2026", - "latex_path": "/latex/1148", - "formalized": true, - "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/1148.lean", - "oeis_urls": [ - "https://oeis.org/A390380", - "https://oeis.org/A393168" - ], - "comments_problem_id": 1148, - "comments_count": 6 - }, { "problem_id": 1150, "problem_url": "/1150", @@ -15117,7 +14989,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 1153, - "comments_count": 7 + "comments_count": 10 }, { "problem_id": 1154, @@ -15456,8 +15328,8 @@ "problem_url": "/1174", "status_bucket": "open", "status_dom_id": "open", - "status_label": "OPEN", - "status_detail": "This is open, and cannot be resolved with a finite computation.", + "status_label": "NOT DISPROVABLE", + "status_detail": "Open in general, but there exist models of set theory where the result is true.", "prize_amount": "", "statement": "Does there exist a graph $G$ with no $K_4$ such that every edge colouring of $G$ with countably many colours contains a monochromatic $K_3$? Does there exist a graph $G$ with no $K_{\\aleph_1}$ such that every edge colouring of $G$ with countably many colours contains a monochromatic $K_{\\aleph_0}$?", "tags": [ @@ -15470,7 +15342,7 @@ "formalized_url": "", "oeis_urls": [], "comments_problem_id": 1174, - "comments_count": 1 + "comments_count": 2 }, { "problem_id": 1175, @@ -15498,8 +15370,8 @@ "problem_url": "/1176", "status_bucket": "open", "status_dom_id": "open", - "status_label": "OPEN", - "status_detail": "This is open, and cannot be resolved with a finite computation.", + "status_label": "NOT DISPROVABLE", + "status_detail": "Open in general, but there exist models of set theory where the result is true.", "prize_amount": "", "statement": "Let $G$ be a graph with chromatic number $\\aleph_1$. Is it true that there is a colouring of the edges with $\\aleph_1$ many colours such that, in any countable colouring of the vertices, there exists a vertex colour containing all edge colours?", "tags": [ @@ -15512,7 +15384,7 @@ "formalized_url": "https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectures/ErdosProblems/1176.lean", "oeis_urls": [], "comments_problem_id": 1176, - "comments_count": 0 + "comments_count": 1 }, { "problem_id": 1177, @@ -15556,6 +15428,68 @@ "oeis_urls": [], "comments_problem_id": 1178, "comments_count": 1 + }, + { + "problem_id": 1181, + "problem_url": "/1181", + "status_bucket": "open", + "status_dom_id": "open", + "status_label": "OPEN", + "status_detail": "This is open, and cannot be resolved with a finite computation.", + "prize_amount": "", + "statement": "Let $q(n,k)$ denote the least prime which does not divide $\\prod_{1\\leq i\\leq k}(n+i)$. Is it true that there exists some $c>0$ such that, for all large $n$,\\[q(n,\\log n)<(1-c)(\\log n)^2?\\]", + "tags": [ + "number theory" + ], + "last_edited": "07 March 2026", + "latex_path": "/latex/1181", + "formalized": false, + "formalized_url": "", + "oeis_urls": [], + "comments_problem_id": 1181, + "comments_count": 0 + }, + { + "problem_id": 1182, + "problem_url": "/1182", + "status_bucket": "open", + "status_dom_id": "open", + "status_label": "OPEN", + "status_detail": "This is open, and cannot be resolved with a finite computation.", + "prize_amount": "", + "statement": "Let $f(n)$ be maximal such that there is a connected graph $G$ with $n$ vertices and $f(n)$ edges such that\\[R(K_3,G)= 2n-1.\\]Let $F(n)$ be maximal such that every connected graph $G$ with $n$ vertices and $\\leq F(n)$ edges has\\[R(K_3,G)= 2n-1.\\]Estimate $f(n)$ and $F(n)$. In particular, is it true that $F(n)/n\\to \\infty$?", + "tags": [ + "graph theory", + "ramsey theory" + ], + "last_edited": "", + "latex_path": "/latex/1182", + "formalized": false, + "formalized_url": "", + "oeis_urls": [], + "comments_problem_id": 1182, + "comments_count": 3 + }, + { + "problem_id": 1183, + "problem_url": "/1183", + "status_bucket": "open", + "status_dom_id": "open", + "status_label": "OPEN", + "status_detail": "This is open, and cannot be resolved with a finite computation.", + "prize_amount": "", + "statement": "Let $f(n)$ be maximal such that in any $2$-colouring of the subsets of $\\{1,\\ldots,n\\}$ there is always a monochromatic family of at least $f(n)$ sets which is closed under taking unions and intersections. Estimate $f(n)$. Let $F(n)$ be defined similarly, except that we only require the family be closed under taking unions. Estimate $F(n)$. In particular, is it true that $F(n)\\geq n^{\\omega(n)}$ for some $\\omega(n)\\to \\infty$ as $n\\to \\infty$, and $F(n)<(1+o(1))^n$?", + "tags": [ + "combinatorics", + "ramsey theory" + ], + "last_edited": "", + "latex_path": "/latex/1183", + "formalized": false, + "formalized_url": "", + "oeis_urls": [], + "comments_problem_id": 1183, + "comments_count": 10 } ] }