proposition: Lemma nf_intro : forall a b n c, nf a -> nf b -> c t2< [a,b ] -> nf c -> nf (gcons a b n c).
proof: Proof. destruct c;constructor;auto with T2. inversion_clear H1;auto with T2. - inversion H3. - inversion H3. Qed.
imports: Coq(Arith List Lia Compare_dec Relations Wellfounded RelationClasses) hydras(Epsilon0) hydras(More_Arith Restriction) hydras(ON_Generic) hydras(rpo.term rpo.rpo) hydras(T2) hydras(Compat815)