proposition: Lemma ex1_prop5b i (H: sub (Vg Jf i) (psI S)): inc i L -> prl_same_data (prl_restr H) (ex1_systemi i).
proof: Proof. by move => iL;rewrite /ex1_systemi; case: (ixm (inc i L)). Qed.
imports: mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat)