Metamath Proof Explorer


Theorem 2reurmo

Description: Double restricted quantification with restricted existential uniqueness and restricted "at most one", analogous to 2eumo . (Contributed by Alexander van der Vekens, 24-Jun-2017)

Ref Expression
Assertion 2reurmo
|- ( E! x e. A E* y e. B ph -> E* x e. A E! y e. B ph )

Proof

Step Hyp Ref Expression
1 reuimrmo
 |-  ( A. x e. A ( E! y e. B ph -> E* y e. B ph ) -> ( E! x e. A E* y e. B ph -> E* x e. A E! y e. B ph ) )
2 reurmo
 |-  ( E! y e. B ph -> E* y e. B ph )
3 2 a1i
 |-  ( x e. A -> ( E! y e. B ph -> E* y e. B ph ) )
4 1 3 mprg
 |-  ( E! x e. A E* y e. B ph -> E* x e. A E! y e. B ph )