proposition: Lemma numfield0 : numfield 0 = [the splittingFieldType rat of rat^o].
proof: Proof. by rewrite /numfield; case: splitting_num_field => //= ? [? [_ ->]]. Qed.
imports: HB(structures) mathcomp(all_ssreflect all_fingroup all_algebra) mathcomp(all_solvable all_field polyrcf) Abel(various classic_ext map_gal algR) Abel(char0 cyclotomic_ext real_closed_ext)