Theorem s1prc 14792

Description: Value of a singleton word if the symbol is a proper class. (Contributed by AV, 26-Mar-2022.)

Assertion

Ref	Expression
s1prc	⊢ (¬ 𝐴 ∈ V → ⟨“𝐴”⟩ = ⟨“∅”⟩)

Proof of Theorem s1prc

Step	Hyp	Ref	Expression
1		ids1 14785	. 2 ⊢ ⟨“𝐴”⟩ = ⟨“( I ‘𝐴)”⟩
2		fvprc 6908	. . 3 ⊢ (¬ 𝐴 ∈ V → ( I ‘𝐴) = ∅)
3	2	s1eqd 14789	. 2 ⊢ (¬ 𝐴 ∈ V → ⟨“( I ‘𝐴)”⟩ = ⟨“∅”⟩)
4	1, 3	eqtrid 2810	1 ⊢ (¬ 𝐴 ∈ V → ⟨“𝐴”⟩ = ⟨“∅”⟩)

This proof depends on syntax axioms:  ¬ wn 3   → wi 4   = wceq 1570   ∈ wcel 2147  Vcvv 3454  ∅c0 4281   I cid 5552  ‘cfv 6566  ⟨“cs1 14783

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1828  ax-4 1842  ax-5 1945  ax-6 2002  ax-7 2043  ax-8 2149  ax-9 2157  ax-10 2180  ax-12 2216  ax-ext 2735  ax-sep 5255  ax-nul 5266  ax-pr 5398

This proof depends on definitions:  df-bi 210  df-an 402  df-or 862  df-3an 1105  df-tru 1573  df-fal 1583  df-ex 1813  df-nf 1817  df-sb 2102  df-mo 2567  df-eu 2597  df-clab 2742  df-cleq 2755  df-clel 2839  df-ne 2960  df-ral 3081  df-rex 3091  df-rab 3417  df-v 3456  df-ss 3901  df-dif 4050  df-in 4094  df-un 4154  df-nul 4282  df-if 4486  df-sn 4589  df-pr 4591  df-op 4841  df-uni 4873  df-br 5109  df-opab 5174  df-id 5553  df-xp 5664  df-rel 5665  df-cnv 5666  df-co 5667  df-dm 5668  df-iota 6520  df-fun 6568  df-fv 6574  df-s1 14784

This theorem is used by: (None)