fact: Definition geigenspace n (g : 'M_n) a := kermxpoly g (('X - a%:P) ^+ n).
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat choice seq) mathcomp(div fintype tuple finfun bigop fingroup perm) mathcomp(ssralg zmodp matrix mxalgebra poly polydiv)