NFE Home New Foundations Explorer < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  NFE Home  >  Th. List  >  hbsb Unicode version

Theorem hbsb 2110
Description: If is not free in , it is not free in when and are distinct. (Contributed by NM, 12-Aug-1993.)
Hypothesis
Ref Expression
hbsb.1
Assertion
Ref Expression
hbsb
Distinct variable group:   ,
Allowed substitution hints:   (,,)

Proof of Theorem hbsb
StepHypRef Expression
1 hbsb.1 . . . 4
21nfi 1551 . . 3  F/
32nfsb 2109 . 2  F/
43nfri 1762 1
Colors of variables: wff setvar class
Syntax hints:   wi 4  wal 1540  wsb 1648
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
This theorem depends on definitions:  df-bi 177  df-an 360  df-tru 1319  df-ex 1542  df-nf 1545  df-sb 1649
This theorem is referenced by:  hbab  2344  hblem  2457
  Copyright terms: Public domain W3C validator