proposition: Lemma Acc_zero : Acc LT zero.
proof: Proof. split; intros y (H1, (H2, H3)). destruct (not_lt_zero H2). 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)