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Theorem nfrab 2792
Description: A variable not free in a wff remains so in a restricted class abstraction. (Contributed by NM, 13-Oct-2003.) (Revised by Mario Carneiro, 9-Oct-2016.)
Hypotheses
Ref Expression
nfrab.1  F/
nfrab.2  F/_
Assertion
Ref Expression
nfrab  F/_

Proof of Theorem nfrab
Dummy variable is distinct from all other variables.
StepHypRef Expression
1 df-rab 2623 . 2
2 nftru 1554 . . . 4  F/
3 nfrab.2 . . . . . . . 8  F/_
43nfcri 2483 . . . . . . 7  F/
5 eleq1 2413 . . . . . . 7
64, 5dvelimnf 2017 . . . . . 6  F/
7 nfrab.1 . . . . . . 7  F/
87a1i 10 . . . . . 6  F/
96, 8nfand 1822 . . . . 5  F/
109adantl 452 . . . 4  F/
112, 10nfabd2 2507 . . 3  F/_
1211trud 1323 . 2  F/_
131, 12nfcxfr 2486 1  F/_
Colors of variables: wff setvar class
Syntax hints:   wn 3   wa 358   wtru 1316  wal 1540   F/wnf 1544   wceq 1642   wcel 1710  cab 2339   F/_wnfc 2476  crab 2618
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
This theorem depends on definitions:  df-bi 177  df-or 359  df-an 360  df-tru 1319  df-ex 1542  df-nf 1545  df-sb 1649  df-clab 2340  df-cleq 2346  df-clel 2349  df-nfc 2478  df-rab 2623
This theorem is referenced by: (None)
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