proposition: Lemma lt_not_eq : forall m1 m2 : t, lt m1 m2 -> ~ eq m1 m2.
proof: Proof. intros m1 m2; rewrite lt_slt, eq_seq; unfold slt, seq; intros; apply LO.lt_not_eq; auto. Qed.
imports: FunInd Recdef FMapInterface FMapList ZArith Int FMapAVL Lia