proposition: Lemma eq_eqdgcdsr : forall p q, p = q -> gcdsr p %= gcdsr q.
proof: Proof. by move=> p q ->. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat div seq) mathcomp(path choice fintype tuple finset ssralg) mathcomp(matrix poly) mathcomp(bigop polydiv) CoqEAL(stronglydiscrete dvdring)