proposition: Lemma fullrankfun_inj : injective frf.
proof: Proof. by move=> i j; rewrite !ffunE => /maxrankfun_inj /(congr1 val)/= /val_inj. 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)