let E be set ; for A being Subset of (E ^omega )
for m, n being Nat holds (A |^ m,n) ^^ (A + ) = (A + ) ^^ (A |^ m,n)
let A be Subset of (E ^omega ); for m, n being Nat holds (A |^ m,n) ^^ (A + ) = (A + ) ^^ (A |^ m,n)
let m, n be Nat; (A |^ m,n) ^^ (A + ) = (A + ) ^^ (A |^ m,n)
thus (A |^ m,n) ^^ (A + ) =
(A |^ m,n) ^^ (A |^.. 1)
by Th50
.=
(A |^.. 1) ^^ (A |^ m,n)
by Th25
.=
(A + ) ^^ (A |^ m,n)
by Th50
; verum