proposition: Theorem M22mult_monoid : monoid_theory MU22 ID_22.
proof: Proof. Proof using R_is_ring. exists. + apply M22mult_one_l. + apply M22mult_one_r. + apply M22mul_assoc. Qed.
imports: Arith ZArith Undecidability.Shared.Libs.DLW.Utils(utils_tac gcd prime binomial sums)