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Theorem 0nelopab 5568
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 Gino Giotto, 3-Oct-2024.)
Assertion
Ref Expression
0nelopab ¬ ∅ ∈ {⟨𝑥, 𝑦⟩ ∣ 𝜑}

Proof of Theorem 0nelopab
StepHypRef Expression
1 vex 3479 . . . . . . 7 𝑥 ∈ V
2 vex 3479 . . . . . . 7 𝑦 ∈ V
31, 2opnzi 5475 . . . . . 6 𝑥, 𝑦⟩ ≠ ∅
43nesymi 2999 . . . . 5 ¬ ∅ = ⟨𝑥, 𝑦
54intnanr 489 . . . 4 ¬ (∅ = ⟨𝑥, 𝑦⟩ ∧ 𝜑)
65nex 1803 . . 3 ¬ ∃𝑦(∅ = ⟨𝑥, 𝑦⟩ ∧ 𝜑)
76nex 1803 . 2 ¬ ∃𝑥𝑦(∅ = ⟨𝑥, 𝑦⟩ ∧ 𝜑)
8 elopab 5528 . 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 397   = wceq 1542  wex 1782  wcel 2107  c0 4323  cop 4635  {copab 5211
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1798  ax-4 1812  ax-5 1914  ax-6 1972  ax-7 2012  ax-8 2109  ax-9 2117  ax-ext 2704  ax-sep 5300  ax-nul 5307  ax-pr 5428
This theorem depends on definitions:  df-bi 206  df-an 398  df-or 847  df-3an 1090  df-tru 1545  df-fal 1555  df-ex 1783  df-sb 2069  df-clab 2711  df-cleq 2725  df-clel 2811  df-ne 2942  df-v 3477  df-dif 3952  df-un 3954  df-in 3956  df-ss 3966  df-nul 4324  df-if 4530  df-sn 4630  df-pr 4632  df-op 4636  df-opab 5212
This theorem is referenced by:  brabv  5570  epelg  5582  satf0n0  34369  bj-0nelmpt  35997
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