proposition: Lemma polyseqK p : Poly p = p.
proof: Proof. by apply: poly_inj; apply: PolyK (valP p). Qed.
imports: HB(structures) mathcomp(ssreflect ssrbool ssrfun eqtype ssrnat seq choice) mathcomp(fintype bigop finset tuple) mathcomp(div ssralg countalg binomial)