fact: Definition coeff_prodgen d (la mu : 'P_d) : R := 'co[cast_intpartn (esym (sumn_intpartn la)) mu].
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