proposition: Lemma col_base_full m n (A : 'M_(m, n)) : row_full (col_base A).
proof: Proof. apply/row_fullP; exists (pid_mx (\rank A) *m invmx (col_ebase A)). by rewrite !mulmxA mulmxKV // pid_mx_id // pid_mx_1. 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)