fact: Definition proper_mxsumP n (S : proper_mxsum_expr n) := let: ProperMxsumExpr _ _ termS := S return mxsum_spec S (proper_mxsum_rank S) in termS.
imports: HB(structures) mathcomp(ssreflect ssrbool ssrfun eqtype ssrnat seq choice) mathcomp(fintype finfun bigop finset fingroup perm order) mathcomp(div prime binomial ssralg finalg zmodp matrix)