proposition: Lemma nf_intro : forall a b n c, nf a -> nf b -> c < [a,b ] -> nf c -> nf (cons a b n c).
proof: Proof. destruct c;constructor;auto with T2. inversion_clear H1;auto with T2. inversion H3. inversion H3. 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