diff --git a/src/lib_crypto_dal/test/test_dal_cryptobox.ml b/src/lib_crypto_dal/test/test_dal_cryptobox.ml
index ffdbecdc6386b099cc1ce52a61fbea49a74a1d83..6fdc9d0ec4556bd8934e0981051330a4a279bcbd 100644
--- a/src/lib_crypto_dal/test/test_dal_cryptobox.ml
+++ b/src/lib_crypto_dal/test/test_dal_cryptobox.ml
@@ -1,5 +1,5 @@
 module Test = struct
-  (* Samples k random integers within the range [0, bound]. *)
+  (* Samples k random integers within the range [0, bound[. *)
   let random_indices bound k =
     let indices = Array.init k (fun _ -> -1) in
     for i = 0 to k - 1 do
@@ -124,9 +124,7 @@ module Test = struct
          let* p = Cryptobox.polynomial_from_slot t slot in
          let enc_shards = Cryptobox.shards_from_polynomial t p in
          let c_indices =
-           random_indices
-             (number_of_shards - 1)
-             (number_of_shards / redundancy_factor)
+           random_indices number_of_shards (number_of_shards / redundancy_factor)
          in
          let c =
            Seq.filter
@@ -160,9 +158,7 @@ module Test = struct
          let* p = Cryptobox.polynomial_from_slot t slot in
          let enc_shards = Cryptobox.shards_from_polynomial t p in
          let c_indices =
-           random_indices
-             (number_of_shards - 1)
-             (number_of_shards / redundancy_factor)
+           random_indices number_of_shards (number_of_shards / redundancy_factor)
          in
          let c =
            Seq.filter
@@ -202,7 +198,7 @@ module Test = struct
      let enc_shards = Cryptobox.shards_from_polynomial t p in
      let c_indices =
        random_indices
-         (number_of_shards - 1)
+         number_of_shards
          ((number_of_shards / redundancy_factor) - 1)
      in
      let c =