diff --git a/README.md b/README.md
index c05d2a0..87cdbe4 100644
--- a/README.md
+++ b/README.md
@@ -411,7 +411,7 @@ var wg sync.WaitGroup
 for i := 0; i < 5; i++ {
 	wg.Add(1)
 	go func() {
-		ids := []string{batches[rand.IntN(2)][rand.IntN(4)], batches[rand.IntN(2)][rand.IntN(4)]}
+		ids := []string{batches[rand.IntN(3)][rand.IntN(5)], batches[rand.IntN(3)][rand.IntN(5)]}
 		res, _ := cacheClient.GetOrFetchBatch(context.Background(), ids, keyPrefixFn, fetchFn)
 		log.Printf("got batch: %v\n", res)
 		wg.Done()
diff --git a/examples/basic/main.go b/examples/basic/main.go
index 69bbfac..a6b9ab2 100644
--- a/examples/basic/main.go
+++ b/examples/basic/main.go
@@ -82,7 +82,7 @@ func demonstrateGetOrFetchBatch(cacheClient *sturdyc.Client[int]) {
 	for i := 0; i < 5; i++ {
 		wg.Add(1)
 		go func() {
-			ids := []string{batches[rand.IntN(2)][rand.IntN(4)], batches[rand.IntN(2)][rand.IntN(4)]}
+			ids := []string{batches[rand.IntN(3)][rand.IntN(5)], batches[rand.IntN(3)][rand.IntN(5)]}
 			res, _ := cacheClient.GetOrFetchBatch(context.Background(), ids, keyPrefixFn, fetchFn)
 			log.Printf("got batch: %v\n", res)
 			wg.Done()