proposition: Lemma intpart_eqP (p q : intpart) : reflect (forall i, nth 0 p i = nth 0 q i) (p == q).
proof: Proof. apply/(iffP eqP) => [-> // |] /part_eqP-/(_ (intpartP p) (intpartP _))/eqP. exact: val_inj. Qed.
imports: HB(structures) mathcomp(all_ssreflect) mathcomp(div ssralg ssrint ssrnum binomial) tools combclass sorted ordtype