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Theorem nfrab1 2732
Description: The abstraction variable in a restricted class abstraction isn't free. (Contributed by NM, 19-Mar-1997.)
Assertion
Ref Expression
nfrab1 𝑥{𝑥𝐴𝜑}

Proof of Theorem nfrab1
StepHypRef Expression
1 df-rab 2537 . 2 {𝑥𝐴𝜑} = {𝑥 ∣ (𝑥𝐴𝜑)}
2 nfab1 2394 . 2 𝑥{𝑥 ∣ (𝑥𝐴𝜑)}
31, 2nfcxfr 2389 1 𝑥{𝑥𝐴𝜑}
Colors of variables:    wff set class
This proof depends on syntax axioms:  wa 104  wcel 2209  {cab 2224  wnfc 2379  {crab 2532
This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-5 1500  ax-gen 1502  ax-ie1 1546  ax-ie2 1547  ax-8 1557  ax-11 1559  ax-4 1563  ax-17 1579  ax-i9 1583  ax-ial 1587  ax-ext 2220
This proof depends on definitions:  df-bi 117  df-nf 1514  df-sb 1816  df-clab 2225  df-cleq 2231  df-clel 2234  df-nfc 2381  df-rab 2537
This theorem is used by:  repizf2  4299  rabxfrd  4615  onintrab2im  4665  tfis  4730  fvmptssdm  5790  infssuzcldc  10668  nnwosdc  12816  ballotfilem7  13279  ballotfilemth  13281  imasnopn  15400  lfgrnloopen  16374
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