proposition: Fact part_ordinal0 : partition (T := T) set0 set0.
proof: Proof. apply/and3P; split. - by rewrite /cover big_set0. - by rewrite /trivIset /cover !big_set0 cards0. - by rewrite in_set0. Qed.
imports: HB(structures) mathcomp(all_ssreflect) mathcomp(div ssralg ssrint ssrnum binomial) tools combclass sorted ordtype partition