Intuitionistic Logic Explorer < Previous   Next > Nearby theorems Mirrors  >  Home  >  ILE Home  >  Th. List  >  nfss Unicode version

Theorem nfss 3058
 Description: If is not free in and , it is not free in . (Contributed by NM, 27-Dec-1996.)
Hypotheses
Ref Expression
dfss2f.1
dfss2f.2
Assertion
Ref Expression
nfss

Proof of Theorem nfss
StepHypRef Expression
1 dfss2f.1 . . 3
2 dfss2f.2 . . 3
31, 2dfss3f 3057 . 2
4 nfra1 2441 . 2
53, 4nfxfr 1433 1
 Colors of variables: wff set class Syntax hints:  wnf 1419   wcel 1463  wnfc 2243  wral 2391   wss 3039 This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-io 681  ax-5 1406  ax-7 1407  ax-gen 1408  ax-ie1 1452  ax-ie2 1453  ax-8 1465  ax-10 1466  ax-11 1467  ax-i12 1468  ax-bndl 1469  ax-4 1470  ax-17 1489  ax-i9 1493  ax-ial 1497  ax-i5r 1498  ax-ext 2097 This theorem depends on definitions:  df-bi 116  df-nf 1420  df-sb 1719  df-clab 2102  df-cleq 2108  df-clel 2111  df-nfc 2245  df-ral 2396  df-in 3045  df-ss 3052 This theorem is referenced by:  ssrexf  3127  nfpw  3491  ssiun2s  3825  triun  4007  ssopab2b  4166  nffrfor  4238  tfis  4465  nfrel  4592  nffun  5114  nff  5237  fvmptssdm  5471  ssoprab2b  5794  nfsum1  11065  nfsum  11066
 Copyright terms: Public domain W3C validator