proposition: Lemma nf_coeff_irrelevance : forall a b n p, nf (cons a n b) -> nf (cons a p b).
proof: Proof. intros; apply nf_intro. - eapply nf_inv1; eauto. - eapply nf_inv2; eauto. - eapply lt_a_phi0_b_intro; eauto. Qed.
imports: Coq(Arith Max Bool Lia Compare_dec Relations Ensembles Wellfounded Bool RelationClasses Operators_Properties ArithRing Logic.Eqdep_dec) hydras(More_Arith Restriction DecPreOrder) hydras(OrdNotations)