Local Open Scope logic.
(*Require Import tweetnacl20140427.split_array_lemmas.*)
unfold Byte.max_unsigned, Int.max_unsigned. simpl. omega. Qed.

Lemma app_Znth1: forall (A : Type){d: Inhabitant A} (l l' : list A) (n :Z),
(n < Zlength l) -> Znth n (l ++ l') = Znth n l.