fact: Definition bdet n (M : 'M[R]_(1 + n)) := (char_poly_alt (-M))`_0.
imports: mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat div seq path ssralg) mathcomp(fintype perm choice matrix bigop zmodp poly polydiv mxpoly) CoqEAL(ssrcomplements minor dvdring) polydvd