fact: Definition EPpermi_prop ph n := [/\ function ph, source ph = n, sub (target ph) Nat & (forall i j, i <c n -> j <c n -> (glt r1 (Vf f i) (Vf f j) <-> glt r2 (Vf g (Vf ph i)) (Vf g (Vf ph j))))].
imports: mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat)