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Theorem nfcr 2481
Description: Consequence of the not-free predicate. (Contributed by Mario Carneiro, 11-Aug-2016.)
Assertion
Ref Expression
nfcr (xA → Ⅎx y A)
Distinct variable groups:   x,y   y,A
Allowed substitution hint:   A(x)

Proof of Theorem nfcr
StepHypRef Expression
1 df-nfc 2478 . 2 (xAyx y A)
2 sp 1747 . 2 (yx y A → Ⅎx y A)
31, 2sylbi 187 1 (xA → Ⅎx y A)
Colors of variables: wff setvar class
Syntax hints:  wi 4  wal 1540  wnf 1544   wcel 1710  wnfc 2476
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-11 1746
This theorem depends on definitions:  df-bi 177  df-ex 1542  df-nfc 2478
This theorem is referenced by:  nfcrii  2482  nfcrd  2502  abidnf  3005  csbtt  3148  csbnestgf  3184
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