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Theorem 0nelopab 5521
Description: The empty set is never an element in an ordered-pair class abstraction. (Contributed by Alexander van der Vekens, 5-Nov-2017.) Reduce axiom usage and shorten proof. (Revised by GG, 3-Oct-2024.)
Assertion
Ref Expression
0nelopab ¬ ∅ ∈ {⟨𝑥, 𝑦⟩ ∣ 𝜑}

Proof of Theorem 0nelopab
StepHypRef Expression
1 vex 3446 . . . . . . 7 𝑥 ∈ V
2 vex 3446 . . . . . . 7 𝑦 ∈ V
31, 2opnzi 5430 . . . . . 6 𝑥, 𝑦⟩ ≠ ∅
43nesymi 2990 . . . . 5 ¬ ∅ = ⟨𝑥, 𝑦
54intnanr 487 . . . 4 ¬ (∅ = ⟨𝑥, 𝑦⟩ ∧ 𝜑)
65nex 1802 . . 3 ¬ ∃𝑦(∅ = ⟨𝑥, 𝑦⟩ ∧ 𝜑)
76nex 1802 . 2 ¬ ∃𝑥𝑦(∅ = ⟨𝑥, 𝑦⟩ ∧ 𝜑)
8 elopab 5483 . 2 (∅ ∈ {⟨𝑥, 𝑦⟩ ∣ 𝜑} ↔ ∃𝑥𝑦(∅ = ⟨𝑥, 𝑦⟩ ∧ 𝜑))
97, 8mtbir 323 1 ¬ ∅ ∈ {⟨𝑥, 𝑦⟩ ∣ 𝜑}
Colors of variables: wff setvar class
Syntax hints:  ¬ wn 3  wa 395   = wceq 1542  wex 1781  wcel 2114  c0 4287  cop 4588  {copab 5162
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1797  ax-4 1811  ax-5 1912  ax-6 1969  ax-7 2010  ax-8 2116  ax-9 2124  ax-ext 2709  ax-sep 5243  ax-pr 5379
This theorem depends on definitions:  df-bi 207  df-an 396  df-or 849  df-3an 1089  df-tru 1545  df-fal 1555  df-ex 1782  df-sb 2069  df-clab 2716  df-cleq 2729  df-clel 2812  df-ne 2934  df-rab 3402  df-v 3444  df-dif 3906  df-un 3908  df-in 3910  df-ss 3920  df-nul 4288  df-if 4482  df-sn 4583  df-pr 4585  df-op 4589  df-opab 5163
This theorem is referenced by:  brabv  5522  epelg  5533  satf0n0  35594  bj-0nelmpt  37369
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