fact: Definition factor (M N P : {fpmod R}) (phi : 'Mor(N,P)) (psi : 'Mor(M,P)) : 'Mor(M,N) := if (kernel phi %= 0) =P true is ReflectT phi_inj then if factor_proof (Monomorphism phi_inj) psi is ReflectT P then projT1 (sig_eqW P) else 0 else 0.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat div seq path) mathcomp(ssralg fintype perm choice matrix bigop zmodp mxalgebra poly) ssrcomplements stronglydiscrete coherent edr