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Theorem onintrab2im 4495
Description: An existence condition which implies an intersection is an ordinal number. (Contributed by Jim Kingdon, 30-Aug-2021.)
Assertion
Ref Expression
onintrab2im  |-  ( E. x  e.  On  ph  ->  |^| { x  e.  On  |  ph }  e.  On )

Proof of Theorem onintrab2im
Dummy variable  y is distinct from all other variables.
StepHypRef Expression
1 ssrab2 3227 . 2  |-  { x  e.  On  |  ph }  C_  On
2 nfrab1 2645 . . . . 5  |-  F/_ x { x  e.  On  |  ph }
32nfcri 2302 . . . 4  |-  F/ x  y  e.  { x  e.  On  |  ph }
43nfex 1625 . . 3  |-  F/ x E. y  y  e.  { x  e.  On  |  ph }
5 rabid 2641 . . . . 5  |-  ( x  e.  { x  e.  On  |  ph }  <->  ( x  e.  On  /\  ph ) )
6 elex2 2742 . . . . 5  |-  ( x  e.  { x  e.  On  |  ph }  ->  E. y  y  e. 
{ x  e.  On  |  ph } )
75, 6sylbir 134 . . . 4  |-  ( ( x  e.  On  /\  ph )  ->  E. y 
y  e.  { x  e.  On  |  ph }
)
87ex 114 . . 3  |-  ( x  e.  On  ->  ( ph  ->  E. y  y  e. 
{ x  e.  On  |  ph } ) )
94, 8rexlimi 2576 . 2  |-  ( E. x  e.  On  ph  ->  E. y  y  e. 
{ x  e.  On  |  ph } )
10 onintonm 4494 . 2  |-  ( ( { x  e.  On  |  ph }  C_  On  /\ 
E. y  y  e. 
{ x  e.  On  |  ph } )  ->  |^| { x  e.  On  |  ph }  e.  On )
111, 9, 10sylancr 411 1  |-  ( E. x  e.  On  ph  ->  |^| { x  e.  On  |  ph }  e.  On )
Colors of variables: wff set class
Syntax hints:    -> wi 4    /\ wa 103   E.wex 1480    e. wcel 2136   E.wrex 2445   {crab 2448    C_ wss 3116   |^|cint 3824   Oncon0 4341
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-io 699  ax-5 1435  ax-7 1436  ax-gen 1437  ax-ie1 1481  ax-ie2 1482  ax-8 1492  ax-10 1493  ax-11 1494  ax-i12 1495  ax-bndl 1497  ax-4 1498  ax-17 1514  ax-i9 1518  ax-ial 1522  ax-i5r 1523  ax-13 2138  ax-14 2139  ax-ext 2147  ax-sep 4100  ax-pow 4153  ax-pr 4187  ax-un 4411
This theorem depends on definitions:  df-bi 116  df-3an 970  df-tru 1346  df-nf 1449  df-sb 1751  df-clab 2152  df-cleq 2158  df-clel 2161  df-nfc 2297  df-ral 2449  df-rex 2450  df-rab 2453  df-v 2728  df-un 3120  df-in 3122  df-ss 3129  df-pw 3561  df-sn 3582  df-pr 3583  df-uni 3790  df-int 3825  df-tr 4081  df-iord 4344  df-on 4346  df-suc 4349
This theorem is referenced by:  cardcl  7137
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