proposition: Lemma prl_r3_res2 i j: gle prl_r3_nr i j -> function_prop (prl_r3_gij (J i j)) (prl_r3_Fl j) (prl_r3_Fl i).
proof: Proof. move =>/prl_r3_prop7/lf_function ff; rewrite/prl_r3_gij; saw. Qed.
imports: mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat)