proposition: Lemma lt_size_deriv (p : {poly R}) : p != 0 -> size p^`() < size p.
proof: Proof. by move=> /polySpred->; apply: size_poly. Qed.
imports: HB(structures) mathcomp(ssreflect ssrbool ssrfun eqtype ssrnat seq choice) mathcomp(fintype bigop finset tuple) mathcomp(div ssralg countalg binomial)