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Theorem cc1 7483
Description: Countable choice in terms of a choice function on a countably infinite set of inhabited sets. (Contributed by Jim Kingdon, 27-Apr-2024.)
Assertion
Ref Expression
cc1  |-  (CCHOICE  ->  A. x
( ( x  ~~  om 
/\  A. z  e.  x  E. w  w  e.  z )  ->  E. f A. z  e.  x  ( f `  z
)  e.  z ) )
Distinct variable groups:    w, f, z   
x, f, z

Proof of Theorem cc1
Dummy variable  a is distinct from all other variables.
StepHypRef Expression
1 simpl 109 . . . . . 6  |-  ( (CCHOICE  /\  ( x  ~~  om  /\  A. z  e.  x  E. w  w  e.  z
) )  -> CCHOICE )
2 simprl 531 . . . . . 6  |-  ( (CCHOICE  /\  ( x  ~~  om  /\  A. z  e.  x  E. w  w  e.  z
) )  ->  x  ~~  om )
3 simprr 533 . . . . . . 7  |-  ( (CCHOICE  /\  ( x  ~~  om  /\  A. z  e.  x  E. w  w  e.  z
) )  ->  A. z  e.  x  E. w  w  e.  z )
4 elequ2 2207 . . . . . . . . 9  |-  ( z  =  a  ->  (
w  e.  z  <->  w  e.  a ) )
54exbidv 1873 . . . . . . . 8  |-  ( z  =  a  ->  ( E. w  w  e.  z 
<->  E. w  w  e.  a ) )
65cbvralvw 2771 . . . . . . 7  |-  ( A. z  e.  x  E. w  w  e.  z  <->  A. a  e.  x  E. w  w  e.  a
)
73, 6sylib 122 . . . . . 6  |-  ( (CCHOICE  /\  ( x  ~~  om  /\  A. z  e.  x  E. w  w  e.  z
) )  ->  A. a  e.  x  E. w  w  e.  a )
81, 2, 7ccfunen 7482 . . . . 5  |-  ( (CCHOICE  /\  ( x  ~~  om  /\  A. z  e.  x  E. w  w  e.  z
) )  ->  E. f
( f  Fn  x  /\  A. a  e.  x  ( f `  a
)  e.  a ) )
9 exsimpr 1666 . . . . 5  |-  ( E. f ( f  Fn  x  /\  A. a  e.  x  ( f `  a )  e.  a )  ->  E. f A. a  e.  x  ( f `  a
)  e.  a )
108, 9syl 14 . . . 4  |-  ( (CCHOICE  /\  ( x  ~~  om  /\  A. z  e.  x  E. w  w  e.  z
) )  ->  E. f A. a  e.  x  ( f `  a
)  e.  a )
11 fveq2 5639 . . . . . . 7  |-  ( a  =  z  ->  (
f `  a )  =  ( f `  z ) )
12 id 19 . . . . . . 7  |-  ( a  =  z  ->  a  =  z )
1311, 12eleq12d 2302 . . . . . 6  |-  ( a  =  z  ->  (
( f `  a
)  e.  a  <->  ( f `  z )  e.  z ) )
1413cbvralvw 2771 . . . . 5  |-  ( A. a  e.  x  (
f `  a )  e.  a  <->  A. z  e.  x  ( f `  z
)  e.  z )
1514exbii 1653 . . . 4  |-  ( E. f A. a  e.  x  ( f `  a )  e.  a  <->  E. f A. z  e.  x  ( f `  z )  e.  z )
1610, 15sylib 122 . . 3  |-  ( (CCHOICE  /\  ( x  ~~  om  /\  A. z  e.  x  E. w  w  e.  z
) )  ->  E. f A. z  e.  x  ( f `  z
)  e.  z )
1716ex 115 . 2  |-  (CCHOICE  ->  (
( x  ~~  om  /\ 
A. z  e.  x  E. w  w  e.  z )  ->  E. f A. z  e.  x  ( f `  z
)  e.  z ) )
1817alrimiv 1922 1  |-  (CCHOICE  ->  A. x
( ( x  ~~  om 
/\  A. z  e.  x  E. w  w  e.  z )  ->  E. f A. z  e.  x  ( f `  z
)  e.  z ) )
Colors of variables: wff set class
Syntax hints:    -> wi 4    /\ wa 104   A.wal 1395   E.wex 1540    e. wcel 2202   A.wral 2510   class class class wbr 4088   omcom 4688    Fn wfn 5321   ` cfv 5326    ~~ cen 6906  CCHOICEwacc 7480
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-io 716  ax-5 1495  ax-7 1496  ax-gen 1497  ax-ie1 1541  ax-ie2 1542  ax-8 1552  ax-10 1553  ax-11 1554  ax-i12 1555  ax-bndl 1557  ax-4 1558  ax-17 1574  ax-i9 1578  ax-ial 1582  ax-i5r 1583  ax-13 2204  ax-14 2205  ax-ext 2213  ax-coll 4204  ax-sep 4207  ax-pow 4264  ax-pr 4299  ax-un 4530
This theorem depends on definitions:  df-bi 117  df-3an 1006  df-tru 1400  df-nf 1509  df-sb 1811  df-eu 2082  df-mo 2083  df-clab 2218  df-cleq 2224  df-clel 2227  df-nfc 2363  df-ral 2515  df-rex 2516  df-reu 2517  df-rab 2519  df-v 2804  df-sbc 3032  df-csb 3128  df-un 3204  df-in 3206  df-ss 3213  df-pw 3654  df-sn 3675  df-pr 3676  df-op 3678  df-uni 3894  df-iun 3972  df-br 4089  df-opab 4151  df-mpt 4152  df-id 4390  df-xp 4731  df-rel 4732  df-cnv 4733  df-co 4734  df-dm 4735  df-rn 4736  df-res 4737  df-ima 4738  df-iota 5286  df-fun 5328  df-fn 5329  df-f 5330  df-f1 5331  df-fo 5332  df-f1o 5333  df-fv 5334  df-en 6909  df-cc 7481
This theorem is referenced by: (None)
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