Theorem uspgrf 29117

Description: The edge function of a simple pseudograph is a one-to-one function into unordered pairs of vertices. (Contributed by Alexander van der Vekens, 10-Aug-2017.) (Revised by AV, 13-Oct-2020.)

Hypotheses

Ref	Expression
isuspgr.v	⊢ 𝑉 = (Vtx‘𝐺)
isuspgr.e	⊢ 𝐸 = (iEdg‘𝐺)

Assertion

Ref	Expression
uspgrf	⊢ (𝐺 ∈ USPGraph → 𝐸:dom 𝐸–1-1→{𝑥 ∈ (𝒫 𝑉 ∖ {∅}) ∣ (♯‘𝑥) ≤ 2})

Distinct variable groups:   𝑥,𝐺   𝑥,𝑉

Allowed substitution hint:   𝐸(𝑥)

Proof of Theorem uspgrf

Step	Hyp	Ref	Expression
1		isuspgr.v	. . 3 ⊢ 𝑉 = (Vtx‘𝐺)
2		isuspgr.e	. . 3 ⊢ 𝐸 = (iEdg‘𝐺)
3	1, 2	isuspgr 29115	. 2 ⊢ (𝐺 ∈ USPGraph → (𝐺 ∈ USPGraph ↔ 𝐸:dom 𝐸–1-1→{𝑥 ∈ (𝒫 𝑉 ∖ {∅}) ∣ (♯‘𝑥) ≤ 2}))
4	3	ibi 267	1 ⊢ (𝐺 ∈ USPGraph → 𝐸:dom 𝐸–1-1→{𝑥 ∈ (𝒫 𝑉 ∖ {∅}) ∣ (♯‘𝑥) ≤ 2})

Syntax hints:   → wi 4   = wceq 1540   ∈ wcel 2109  {crab 3396   ∖ cdif 3902  ∅c0 4286  𝒫 cpw 4553  {csn 4579   class class class wbr 5095  dom cdm 5623  –1-1→wf1 6483  ‘cfv 6486   ≤ cle 11169  2c2 12201  ♯chash 14255  Vtxcvtx 28959  iEdgciedg 28960  USPGraphcuspgr 29111

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1795  ax-4 1809  ax-5 1910  ax-6 1967  ax-7 2008  ax-8 2111  ax-9 2119  ax-ext 2701  ax-nul 5248

This theorem depends on definitions:  df-bi 207  df-an 396  df-or 848  df-3an 1088  df-tru 1543  df-fal 1553  df-ex 1780  df-sb 2066  df-clab 2708  df-cleq 2721  df-clel 2803  df-ne 2926  df-rab 3397  df-v 3440  df-sbc 3745  df-dif 3908  df-un 3910  df-ss 3922  df-nul 4287  df-if 4479  df-pw 4555  df-sn 4580  df-pr 4582  df-op 4586  df-uni 4862  df-br 5096  df-opab 5158  df-rel 5630  df-cnv 5631  df-co 5632  df-dm 5633  df-rn 5634  df-iota 6442  df-fun 6488  df-fn 6489  df-f 6490  df-f1 6491  df-fv 6494  df-uspgr 29113

This theorem is referenced by:  uspgrf1oedg  29136  usgrumgruspgr  29145  usgruspgrb  29146  usgrislfuspgr  29150  uspgrn2crct  29771