fact: Fixpoint MN_coeff_rec (la nu mu : seq nat) : int := if mu is m0 :: m then foldr (fun psh acc => MN_coeff_rec la psh.1 m * (-1) ^+ psh.2.-1 + acc) 0 [seq psh | psh <- pmap (add_ribbon nu m0.-1) (iota 0 (size la)) & included psh.1 la] else (la == nu).
imports: HB(structures) mathcomp(all_ssreflect) mathcomp(ssralg ssrint perm fingroup tuple vector rat) mathcomp(ssrcomplements freeg mpoly monalg) sorted tools ordtype permuted partition skewpart antisym Schur_mpoly Schur_altdef sympoly homogsym