proposition: Lemma Nth_rev' : forall n x l, n < length l -> Nth (length l - 1 - n) l x -> Nth n (rev l) x.
proof: Proof. Proof using. introv L M. applys_eq (>> Nth_rev M). math. Qed.
imports: Coq.Classes.Morphisms TLC(LibTactics LibLogic LibReflect LibOperation LibProd LibOption LibNat LibInt LibWf LibMonoid LibRelation)