Theorem clnbgrn0 48655

Description: The closed neighborhood of a vertex is never empty. (Contributed by AV, 16-May-2025.)

Hypothesis

Ref	Expression
clnbgrn0.v	⊢ 𝑉 = (Vtx‘𝐺)

Assertion

Ref	Expression
clnbgrn0	⊢ (𝑁 ∈ 𝑉 → (𝐺 ClNeighbVtx 𝑁) ≠ ∅)

Proof of Theorem clnbgrn0

Step	Hyp	Ref	Expression
1		clnbgrn0.v	. . 3 ⊢ 𝑉 = (Vtx‘𝐺)
2	1	clnbgrvtxel 48652	. 2 ⊢ (𝑁 ∈ 𝑉 → 𝑁 ∈ (𝐺 ClNeighbVtx 𝑁))
3		ne0i 4294	. 2 ⊢ (𝑁 ∈ (𝐺 ClNeighbVtx 𝑁) → (𝐺 ClNeighbVtx 𝑁) ≠ ∅)
4	2, 3	syl 18	1 ⊢ (𝑁 ∈ 𝑉 → (𝐺 ClNeighbVtx 𝑁) ≠ ∅)

This proof depends on syntax axioms:   → wi 4   = wceq 1570   ∈ wcel 2146   ≠ wne 2960  ∅c0 4286  ‘cfv 6540  (class class class)co 7419  Vtxcvtx 29401   ClNeighbVtx cclnbgr 48641

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 1943  ax-6 2000  ax-7 2041  ax-8 2148  ax-9 2156  ax-10 2179  ax-11 2195  ax-12 2216  ax-ext 2737  ax-sep 5259  ax-nul 5271  ax-pr 5406  ax-un 7742

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 2100  df-mo 2569  df-eu 2599  df-clab 2744  df-cleq 2757  df-clel 2840  df-nfc 2914  df-ne 2961  df-ral 3082  df-rex 3092  df-rab 3419  df-v 3459  df-sbc 3747  df-csb 3855  df-dif 3909  df-un 3911  df-in 3913  df-ss 3923  df-nul 4287  df-if 4490  df-pw 4566  df-sn 4592  df-pr 4594  df-op 4598  df-uni 4875  df-iun 4960  df-br 5112  df-opab 5176  df-mpt 5195  df-id 5558  df-xp 5669  df-rel 5670  df-cnv 5671  df-co 5672  df-dm 5673  df-rn 5674  df-res 5675  df-ima 5676  df-iota 6496  df-fun 6542  df-fv 6548  df-ov 7422  df-oprab 7423  df-mpo 7424  df-1st 7992  df-2nd 7993  df-clnbgr 48642

This theorem is used by: (None)