proposition: Lemma sdivr_closedM : sdivr_closed -> smulr_closed S.
proof: Proof. by move=> Sdiv; have [_ SM] := divr_closedM (sdivr_closed_div Sdiv); case: Sdiv. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat div seq) mathcomp(choice fintype finfun bigop prime binomial)