proposition: Lemma eigenvectorP {v : 'rV_n} : reflect (exists a, (v <= eigenspace a)%MS) (stablemx v g).
proof: Proof. by apply: (iffP (sub_rVP _ _)) => -[a] /eigenspaceP; exists a. Qed.
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)