diff --git a/racket/collects/racket/list.rkt b/racket/collects/racket/list.rkt
index f37b41feca..38cb2c5ee1 100644
--- a/racket/collects/racket/list.rkt
+++ b/racket/collects/racket/list.rkt
@@ -678,9 +678,8 @@
                   ;; then we change it to #(3 5 6 7)
                   [index-to-change
                    (define val-to-change (add1 (vector-ref k* index-to-change)))
-                   (vector-set! k* index-to-change val-to-change)
-                   (for ([i (in-range (add1 index-to-change) k)]
-                         [v (in-naturals (add1 val-to-change))])
+                   (for ([i (in-range index-to-change k)]
+                         [v (in-naturals val-to-change)])
                      (vector-set! k* i v))]
                   ;; Otherwise, there's no incrementable index. E.g.,
                   ;; N = 10 and we have #(6 7 8 9), so we quit enumeration