fact: Definition monX (mon : 'X_{1.. m*n}) : 'X_{1.. m} := [multinom (\sum_(j < n) mon (mxvec_index i j))%N | i < m].
imports: HB(structures) mathcomp(all_ssreflect) mathcomp(ssrint rat ssralg ssrnum algC matrix vector) mathcomp(mpoly) tools partition ordtype antisym Schur_mpoly Schur_altdef sympoly homogsym permcent