proposition: Lemma ratMult_3_ratAdd : forall r, (3 / 1) * r == r + r + r.
proof: Proof. rattac. inversion H; clear H; subst. inversion H0; clear H0; subst. simpl. arithNormalize. repeat rewrite Nat.mul_0_r. repeat rewrite Nat.add_0_r. trivial. Qed.
imports: micromega.Lia List FCF.StdNat Arith Lia Setoid RelationClasses Coq.Classes.Morphisms