proposition: Lemma ler_pMn2r n : (0 < n)%N -> {mono (@GRing.natmul R)^~ n : x y / x <= y}.
proof: Proof. by case: n => // n _ x y /=; rewrite -mulr_natl -[y *+ _]mulr_natl ler_pM2l. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat seq choice) mathcomp(ssrAC div fintype path bigop order finset fingroup) mathcomp(ssralg poly)