proposition: Lemma mnm_n0E : @all_equal_to 'X_{1..0} 0%MM.
proof: Proof. by move=> mon; apply mnmP => [[i Hi]]. Qed.
imports: HB(structures) mathcomp(all_ssreflect) mathcomp(ssralg ssrint fingroup perm) mathcomp(ssrcomplements freeg mpoly) sorted tools ordtype permuted partition skewpart composition Yamanouchi std tableau stdtab skewtab permcent antisym Schur_mpoly therule Schur_altdef unitriginv