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Theorem nfand 1822
Description: If in a context is not free in and , it is not free in . (Contributed by Mario Carneiro, 7-Oct-2016.)
Hypotheses
Ref Expression
nfand.1  F/
nfand.2  F/
Assertion
Ref Expression
nfand  F/

Proof of Theorem nfand
StepHypRef Expression
1 df-an 360 . 2
2 nfand.1 . . . 4  F/
3 nfand.2 . . . . 5  F/
43nfnd 1791 . . . 4  F/
52, 4nfimd 1808 . . 3  F/
65nfnd 1791 . 2  F/
71, 6nfxfrd 1571 1  F/
Colors of variables: wff setvar class
Syntax hints:   wn 3   wi 4   wa 358   F/wnf 1544
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-11 1746
This theorem depends on definitions:  df-bi 177  df-an 360  df-ex 1542  df-nf 1545
This theorem is referenced by:  nf3and  1823  nfan  1824  nfbid  1832  nfeld  2504  nfreud  2783  nfrmod  2784  nfrmo  2786  nfrab  2792  nfifd  3685  dfid3  4768
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