fact: Definition mxvec (A : 'M[R]_(m, n)) := castmx (erefl _, mxvec_cast) (\row_k A (enum_val k).1 (enum_val k).2).
imports: HB(structures) mathcomp(ssreflect ssrbool ssrfun eqtype ssrnat seq choice) mathcomp(fintype finfun bigop finset fingroup perm order) mathcomp(div prime binomial ssralg countalg finalg zmodp)