proposition: Lemma LE_refl : forall alpha, nf alpha -> alpha t1<= alpha.
proof: Proof. repeat split; eauto with T1. apply le_refl. 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)