fact: Fixpoint coeff_prodgen_seq l : 'P_(sumn l) -> R := if l is l0 :: l' then fun la : 'P_(sumn (l0 :: l')) => \sum_(p | la == p.1 +|+ p.2) co p.1 * coeff_prodgen_seq p.2 else fun _ => 1.
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