proposition: Lemma posnatMult_eq : forall p1 p2, posnatToNat (posnatMult p1 p2) = (p1 * p2)%nat.
proof: Proof. intuition. unfold posnatMult. destruct p1. destruct p2. unfold posnatToNat, natToPosnat. trivial. Qed.
imports: micromega.Lia List FCF.StdNat Arith Lia Setoid RelationClasses Coq.Classes.Morphisms