proposition: Lemma pred_of_cons : forall a b n c, zero < a \/ zero < b -> pred (cons a b n c) = match pred c with Some c' => Some (cons a b n c') |None => None end.
proof: Proof. destruct a. destruct b;simpl. destruct 1;lt_clean. auto. simpl. auto. Qed.
imports: EPSILON0 Arith List Omega Compare_dec Relations Wellfounded Max Tools More_nat AccP not_decreasing EPSILON0 More_nat Gamma0_prelude Gamma0_length term rpo