proposition: Lemma eqCmodMr e : {in Num.int, forall z x y, x == y %[mod e] -> x * z == y * z %[mod e]}%C.
proof: Proof. by move=> z Zz x y; rewrite /eqCmod -mulrBl => /dvdC_mulr->. Qed.
imports: HB(structures) mathcomp(ssreflect ssrbool ssrfun ssrnat eqtype seq choice) mathcomp(div fintype path bigop finset prime order ssralg) mathcomp(poly polydiv mxpoly generic_quotient countalg) mathcomp(ssrnum closed_field ssrint archimedean rat intdiv) mathcomp(algebraics_fundamentals)