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Theorem cc1 7447
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 529 . . . . . 6  |-  ( (CCHOICE  /\  ( x  ~~  om  /\  A. z  e.  x  E. w  w  e.  z
) )  ->  x  ~~  om )
3 simprr 531 . . . . . . 7  |-  ( (CCHOICE  /\  ( x  ~~  om  /\  A. z  e.  x  E. w  w  e.  z
) )  ->  A. z  e.  x  E. w  w  e.  z )
4 elequ2 2205 . . . . . . . . 9  |-  ( z  =  a  ->  (
w  e.  z  <->  w  e.  a ) )
54exbidv 1871 . . . . . . . 8  |-  ( z  =  a  ->  ( E. w  w  e.  z 
<->  E. w  w  e.  a ) )
65cbvralvw 2769 . . . . . . 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 7446 . . . . 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 1664 . . . . 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 5626 . . . . . . 7  |-  ( a  =  z  ->  (
f `  a )  =  ( f `  z ) )
12 id 19 . . . . . . 7  |-  ( a  =  z  ->  a  =  z )
1311, 12eleq12d 2300 . . . . . 6  |-  ( a  =  z  ->  (
( f `  a
)  e.  a  <->  ( f `  z )  e.  z ) )
1413cbvralvw 2769 . . . . 5  |-  ( A. a  e.  x  (
f `  a )  e.  a  <->  A. z  e.  x  ( f `  z
)  e.  z )
1514exbii 1651 . . . 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 1920 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 1393   E.wex 1538    e. wcel 2200   A.wral 2508   class class class wbr 4082   omcom 4681    Fn wfn 5312   ` cfv 5317    ~~ cen 6883  CCHOICEwacc 7444
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 714  ax-5 1493  ax-7 1494  ax-gen 1495  ax-ie1 1539  ax-ie2 1540  ax-8 1550  ax-10 1551  ax-11 1552  ax-i12 1553  ax-bndl 1555  ax-4 1556  ax-17 1572  ax-i9 1576  ax-ial 1580  ax-i5r 1581  ax-13 2202  ax-14 2203  ax-ext 2211  ax-coll 4198  ax-sep 4201  ax-pow 4257  ax-pr 4292  ax-un 4523
This theorem depends on definitions:  df-bi 117  df-3an 1004  df-tru 1398  df-nf 1507  df-sb 1809  df-eu 2080  df-mo 2081  df-clab 2216  df-cleq 2222  df-clel 2225  df-nfc 2361  df-ral 2513  df-rex 2514  df-reu 2515  df-rab 2517  df-v 2801  df-sbc 3029  df-csb 3125  df-un 3201  df-in 3203  df-ss 3210  df-pw 3651  df-sn 3672  df-pr 3673  df-op 3675  df-uni 3888  df-iun 3966  df-br 4083  df-opab 4145  df-mpt 4146  df-id 4383  df-xp 4724  df-rel 4725  df-cnv 4726  df-co 4727  df-dm 4728  df-rn 4729  df-res 4730  df-ima 4731  df-iota 5277  df-fun 5319  df-fn 5320  df-f 5321  df-f1 5322  df-fo 5323  df-f1o 5324  df-fv 5325  df-en 6886  df-cc 7445
This theorem is referenced by: (None)
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