proposition: Lemma prl_r3_prop5b i (H: sub i (psI S)): inc i prl_r3_nI -> prl_same_data (prl_restr H) (prl_r3_systemi i).
proof: Proof. by move => iL;rewrite /prl_r3_systemi; case: (ixm (inc i prl_r3_nI)). Qed.
imports: mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat)