proposition: Lemma polyseq_cons c p : cons_poly c p = (if ~~ nilp p then c :: p else c%:P) :> seq R.
proof: Proof. by case: p => [[]]. Qed.
imports: HB(structures) mathcomp(ssreflect ssrbool ssrfun eqtype ssrnat seq choice) mathcomp(fintype bigop finset tuple) mathcomp(div ssralg countalg binomial)