fact: Definition improve_pivot m n (M : 'M[R]_(1 + m, 1 + n)) := improve_pivot_rec 1 1 (sdvdr_wf (M 0 0)).
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat div seq path) mathcomp(ssralg ssrint ssrnum fintype choice) mathcomp(matrix mxalgebra bigop zmodp perm) dvdring mxstructure stronglydiscrete coherent edr