proposition: Lemma Zp_inv_out x : ~~ coprime p x -> Zp_inv x = x.
proof: Proof. by rewrite /Zp_inv => /negPf->. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool choice eqtype ssrnat seq div) mathcomp(fintype bigop finset prime fingroup) mathcomp(ssralg finalg countalg)