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Theorem ncfinex 4473
Description: The finite cardinality of a set exists. (Contributed by SF, 27-Jan-2015.)
Assertion
Ref Expression
ncfinex Ncfin A V

Proof of Theorem ncfinex
Dummy variable x is distinct from all other variables.
StepHypRef Expression
1 df-ncfin 4443 . 2 Ncfin A = (℩x(x Nn A x))
2 iotaex 4357 . 2 (℩x(x Nn A x)) V
31, 2eqeltri 2423 1 Ncfin A V
Colors of variables: wff setvar class
Syntax hints:   wa 358   wcel 1710  Vcvv 2860  cio 4338   Nn cnnc 4374   Ncfin cncfin 4435
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1546  ax-5 1557  ax-17 1616  ax-9 1654  ax-8 1675  ax-6 1729  ax-7 1734  ax-11 1746  ax-12 1925  ax-ext 2334  ax-nin 4079
This theorem depends on definitions:  df-bi 177  df-or 359  df-an 360  df-nan 1288  df-tru 1319  df-ex 1542  df-nf 1545  df-sb 1649  df-eu 2208  df-clab 2340  df-cleq 2346  df-clel 2349  df-nfc 2479  df-ne 2519  df-ral 2620  df-rex 2621  df-v 2862  df-sbc 3048  df-nin 3212  df-compl 3213  df-in 3214  df-un 3215  df-dif 3216  df-ss 3260  df-nul 3552  df-sn 3742  df-pr 3743  df-uni 3893  df-iota 4340  df-ncfin 4443
This theorem is referenced by:  ncvspfin  4539  vfintle  4547  vfin1cltv  4548  vfinncvntsp  4550  vfinspss  4552  vfinspclt  4553  vfinspeqtncv  4554  vfinncsp  4555
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