proposition: Lemma Zp_mulrn x n : x *+ n = inZp (x * n).
proof: Proof. apply: val_inj => /=; elim: n => [|n IHn]; first by rewrite muln0 modn_small. by rewrite !GRing.mulrS /= IHn modnDmr mulnS. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool choice eqtype ssrnat seq div) mathcomp(fintype bigop finset prime fingroup) mathcomp(ssralg finalg countalg)