fact: Definition mulmx m n p (A : 'M_(m, n)) (B : 'M_(n, p)) := \matrix_(i < m, k < p) \big [radd/0]_(j < n) (A i j * B j k).
imports: ssreflect ssrbool ssrfun eqtype ssrnat seq choice fintype finfun bigops ssralg groups perm zmodp morphisms Ring RingClass bigopsClass Setoid Morphisms