fact: Definition Mp : 'M[{poly {poly int}}]_(2,2) := \matrix_(i,j < 2) (Poly [:: Poly [:: 3%:Z; 0; 1]; 0]).
imports: mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat div seq ssralg) mathcomp(path choice fintype tuple finset bigop poly matrix mxpoly) CoqEAL(hrel param refinements trivial_seq) mathcomp(ssrint poly) CoqEAL(binnat binint seqpoly binord)