proposition: Fact mor_of_mx_inj : kernel (mor_of_mx X) %= 0.
proof: Proof. by apply/monoP=> P psi; rewrite /= /eqmor !subr0 -dvd_ker. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat div seq path) mathcomp(ssralg fintype perm choice matrix bigop zmodp mxalgebra poly) ssrcomplements stronglydiscrete coherent edr