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Lemma join_unage  {A} {JA: Join A}{PA: Perm_alg A}{SA: Sep_alg A}{agA: ageable A}{AgeA: Age_alg A}:
forall (phi3 phi1' phi2' phi3': A),
age1 phi3 = Some phi3' ->
join phi1' phi2' phi3' ->
exists phi1, exists phi2, join phi1 phi2 phi3 /\
age1 phi1 = Some phi1' /\ age1 phi2 = Some phi2'.