proposition: Lemma tricho_lt_4' : forall a1 a2 b1 b2 n1 n2 c1 c2, length (cons a1 b1 0 c1) + length b2 < length (cons a1 b1 n1 c1) + length (cons a2 b2 n2 c2).
proof: Proof. intros; apply plus_le_lt_compat. case n1. auto. intros;apply lt_le_weak;apply length_n; auto with arith. apply length_b. 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