fact: Definition Madd := \matrix_(i,j < 29) (i + j)%:Z%:P.
imports: mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat div seq path ssralg) mathcomp(fintype perm choice matrix bigop zmodp poly polydiv mxpoly) CoqEAL(minor hrel param refinements seqmx) mathcomp(ssrint) CoqEAL(binnat binint seqpoly poly_div binord trivial_seq)