proposition: Lemma hornerMn n p x : (p *+ n).[x] = p.[x] *+ n.
proof: Proof. by elim: n => [| n IHn]; rewrite ?horner0 // !mulrS hornerD IHn. Qed.
imports: HB(structures) mathcomp(ssreflect ssrbool ssrfun eqtype ssrnat seq choice) mathcomp(fintype bigop finset tuple) mathcomp(div ssralg countalg binomial)