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Theorem a17d 1617
Description: ax-17 1616 with antecedent. Useful in proofs of deduction versions of bound-variable hypothesis builders. (Contributed by NM, 1-Mar-2013.)
Ref Expression
a17d (φ → (ψxψ))
Distinct variable group:   ψ,x
Allowed substitution hint:   φ(x)

Proof of Theorem a17d
StepHypRef Expression
1 ax-17 1616 . 2 (ψxψ)
21a1i 10 1 (φ → (ψxψ))
Colors of variables: wff setvar class
Syntax hints:  wi 4  wal 1540
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-17 1616
This theorem is referenced by:  ax12w  1724  dvelimv  1939
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