Theorem cusgredg 26721

Description: In a complete simple graph, the edges are all the pairs of different vertices. (Contributed by Alexander van der Vekens, 12-Jan-2018.) (Revised by AV, 1-Nov-2020.)

Hypotheses

Ref	Expression
iscusgrvtx.v	⊢ 𝑉 = (Vtx‘𝐺)
iscusgredg.v	⊢ 𝐸 = (Edg‘𝐺)

Assertion

Ref	Expression
cusgredg	⊢ (𝐺 ∈ ComplUSGraph → 𝐸 = {𝑥 ∈ 𝒫 𝑉 ∣ (♯‘𝑥) = 2})

Distinct variable groups:   𝑥,𝐺   𝑥,𝑉

Allowed substitution hint:   𝐸(𝑥)

Proof of Theorem cusgredg

Dummy variables 𝑣 𝑛 𝑝 𝑦 𝑧 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		iscusgrvtx.v	. . 3 ⊢ 𝑉 = (Vtx‘𝐺)
2		iscusgredg.v	. . 3 ⊢ 𝐸 = (Edg‘𝐺)
3	1, 2	iscusgredg 26720	. 2 ⊢ (𝐺 ∈ ComplUSGraph ↔ (𝐺 ∈ USGraph ∧ ∀𝑣 ∈ 𝑉 ∀𝑛 ∈ (𝑉 ∖ {𝑣}){𝑛, 𝑣} ∈ 𝐸))
4		usgredgss 26457	. . . . 5 ⊢ (𝐺 ∈ USGraph → (Edg‘𝐺) ⊆ {𝑥 ∈ 𝒫 (Vtx‘𝐺) ∣ (♯‘𝑥) = 2})
5	1	pweqi 4381	. . . . . 6 ⊢ 𝒫 𝑉 = 𝒫 (Vtx‘𝐺)
6		rabeq 3404	. . . . . 6 ⊢ (𝒫 𝑉 = 𝒫 (Vtx‘𝐺) → {𝑥 ∈ 𝒫 𝑉 ∣ (♯‘𝑥) = 2} = {𝑥 ∈ 𝒫 (Vtx‘𝐺) ∣ (♯‘𝑥) = 2})
7	5, 6	ax-mp 5	. . . . 5 ⊢ {𝑥 ∈ 𝒫 𝑉 ∣ (♯‘𝑥) = 2} = {𝑥 ∈ 𝒫 (Vtx‘𝐺) ∣ (♯‘𝑥) = 2}
8	4, 2, 7	3sstr4g 3870	. . . 4 ⊢ (𝐺 ∈ USGraph → 𝐸 ⊆ {𝑥 ∈ 𝒫 𝑉 ∣ (♯‘𝑥) = 2})
9	8	adantr 474	. . 3 ⊢ ((𝐺 ∈ USGraph ∧ ∀𝑣 ∈ 𝑉 ∀𝑛 ∈ (𝑉 ∖ {𝑣}){𝑛, 𝑣} ∈ 𝐸) → 𝐸 ⊆ {𝑥 ∈ 𝒫 𝑉 ∣ (♯‘𝑥) = 2})
10		elss2prb 13557	. . . . 5 ⊢ (𝑝 ∈ {𝑥 ∈ 𝒫 𝑉 ∣ (♯‘𝑥) = 2} ↔ ∃𝑦 ∈ 𝑉 ∃𝑧 ∈ 𝑉 (𝑦 ≠ 𝑧 ∧ 𝑝 = {𝑦, 𝑧}))
11		sneq 4406	. . . . . . . . . . . . . . 15 ⊢ (𝑣 = 𝑦 → {𝑣} = {𝑦})
12	11	difeq2d 3954	. . . . . . . . . . . . . 14 ⊢ (𝑣 = 𝑦 → (𝑉 ∖ {𝑣}) = (𝑉 ∖ {𝑦}))
13		preq2 4486	. . . . . . . . . . . . . . 15 ⊢ (𝑣 = 𝑦 → {𝑛, 𝑣} = {𝑛, 𝑦})
14	13	eleq1d 2890	. . . . . . . . . . . . . 14 ⊢ (𝑣 = 𝑦 → ({𝑛, 𝑣} ∈ 𝐸 ↔ {𝑛, 𝑦} ∈ 𝐸))
15	12, 14	raleqbidv 3363	. . . . . . . . . . . . 13 ⊢ (𝑣 = 𝑦 → (∀𝑛 ∈ (𝑉 ∖ {𝑣}){𝑛, 𝑣} ∈ 𝐸 ↔ ∀𝑛 ∈ (𝑉 ∖ {𝑦}){𝑛, 𝑦} ∈ 𝐸))
16	15	rspcv 3521	. . . . . . . . . . . 12 ⊢ (𝑦 ∈ 𝑉 → (∀𝑣 ∈ 𝑉 ∀𝑛 ∈ (𝑉 ∖ {𝑣}){𝑛, 𝑣} ∈ 𝐸 → ∀𝑛 ∈ (𝑉 ∖ {𝑦}){𝑛, 𝑦} ∈ 𝐸))
17	16	adantr 474	. . . . . . . . . . 11 ⊢ ((𝑦 ∈ 𝑉 ∧ 𝑧 ∈ 𝑉) → (∀𝑣 ∈ 𝑉 ∀𝑛 ∈ (𝑉 ∖ {𝑣}){𝑛, 𝑣} ∈ 𝐸 → ∀𝑛 ∈ (𝑉 ∖ {𝑦}){𝑛, 𝑦} ∈ 𝐸))
18	17	adantr 474	. . . . . . . . . 10 ⊢ (((𝑦 ∈ 𝑉 ∧ 𝑧 ∈ 𝑉) ∧ (𝑦 ≠ 𝑧 ∧ 𝑝 = {𝑦, 𝑧})) → (∀𝑣 ∈ 𝑉 ∀𝑛 ∈ (𝑉 ∖ {𝑣}){𝑛, 𝑣} ∈ 𝐸 → ∀𝑛 ∈ (𝑉 ∖ {𝑦}){𝑛, 𝑦} ∈ 𝐸))
19		simpr 479	. . . . . . . . . . . . 13 ⊢ ((𝑦 ∈ 𝑉 ∧ 𝑧 ∈ 𝑉) → 𝑧 ∈ 𝑉)
20		necom 3051	. . . . . . . . . . . . . . 15 ⊢ (𝑦 ≠ 𝑧 ↔ 𝑧 ≠ 𝑦)
21	20	biimpi 208	. . . . . . . . . . . . . 14 ⊢ (𝑦 ≠ 𝑧 → 𝑧 ≠ 𝑦)
22	21	adantr 474	. . . . . . . . . . . . 13 ⊢ ((𝑦 ≠ 𝑧 ∧ 𝑝 = {𝑦, 𝑧}) → 𝑧 ≠ 𝑦)
23	19, 22	anim12i 608	. . . . . . . . . . . 12 ⊢ (((𝑦 ∈ 𝑉 ∧ 𝑧 ∈ 𝑉) ∧ (𝑦 ≠ 𝑧 ∧ 𝑝 = {𝑦, 𝑧})) → (𝑧 ∈ 𝑉 ∧ 𝑧 ≠ 𝑦))
24		eldifsn 4535	. . . . . . . . . . . 12 ⊢ (𝑧 ∈ (𝑉 ∖ {𝑦}) ↔ (𝑧 ∈ 𝑉 ∧ 𝑧 ≠ 𝑦))
25	23, 24	sylibr 226	. . . . . . . . . . 11 ⊢ (((𝑦 ∈ 𝑉 ∧ 𝑧 ∈ 𝑉) ∧ (𝑦 ≠ 𝑧 ∧ 𝑝 = {𝑦, 𝑧})) → 𝑧 ∈ (𝑉 ∖ {𝑦}))
26		preq1 4485	. . . . . . . . . . . . 13 ⊢ (𝑛 = 𝑧 → {𝑛, 𝑦} = {𝑧, 𝑦})
27	26	eleq1d 2890	. . . . . . . . . . . 12 ⊢ (𝑛 = 𝑧 → ({𝑛, 𝑦} ∈ 𝐸 ↔ {𝑧, 𝑦} ∈ 𝐸))
28	27	rspcv 3521	. . . . . . . . . . 11 ⊢ (𝑧 ∈ (𝑉 ∖ {𝑦}) → (∀𝑛 ∈ (𝑉 ∖ {𝑦}){𝑛, 𝑦} ∈ 𝐸 → {𝑧, 𝑦} ∈ 𝐸))
29	25, 28	syl 17	. . . . . . . . . 10 ⊢ (((𝑦 ∈ 𝑉 ∧ 𝑧 ∈ 𝑉) ∧ (𝑦 ≠ 𝑧 ∧ 𝑝 = {𝑦, 𝑧})) → (∀𝑛 ∈ (𝑉 ∖ {𝑦}){𝑛, 𝑦} ∈ 𝐸 → {𝑧, 𝑦} ∈ 𝐸))
30		id 22	. . . . . . . . . . . . . . . 16 ⊢ (𝑝 = {𝑦, 𝑧} → 𝑝 = {𝑦, 𝑧})
31		prcom 4484	. . . . . . . . . . . . . . . 16 ⊢ {𝑦, 𝑧} = {𝑧, 𝑦}
32	30, 31	syl6req 2877	. . . . . . . . . . . . . . 15 ⊢ (𝑝 = {𝑦, 𝑧} → {𝑧, 𝑦} = 𝑝)
33	32	eleq1d 2890	. . . . . . . . . . . . . 14 ⊢ (𝑝 = {𝑦, 𝑧} → ({𝑧, 𝑦} ∈ 𝐸 ↔ 𝑝 ∈ 𝐸))
34	33	biimpd 221	. . . . . . . . . . . . 13 ⊢ (𝑝 = {𝑦, 𝑧} → ({𝑧, 𝑦} ∈ 𝐸 → 𝑝 ∈ 𝐸))
35	34	a1d 25	. . . . . . . . . . . 12 ⊢ (𝑝 = {𝑦, 𝑧} → (𝐺 ∈ USGraph → ({𝑧, 𝑦} ∈ 𝐸 → 𝑝 ∈ 𝐸)))
36	35	ad2antll 722	. . . . . . . . . . 11 ⊢ (((𝑦 ∈ 𝑉 ∧ 𝑧 ∈ 𝑉) ∧ (𝑦 ≠ 𝑧 ∧ 𝑝 = {𝑦, 𝑧})) → (𝐺 ∈ USGraph → ({𝑧, 𝑦} ∈ 𝐸 → 𝑝 ∈ 𝐸)))
37	36	com23 86	. . . . . . . . . 10 ⊢ (((𝑦 ∈ 𝑉 ∧ 𝑧 ∈ 𝑉) ∧ (𝑦 ≠ 𝑧 ∧ 𝑝 = {𝑦, 𝑧})) → ({𝑧, 𝑦} ∈ 𝐸 → (𝐺 ∈ USGraph → 𝑝 ∈ 𝐸)))
38	18, 29, 37	3syld 60	. . . . . . . . 9 ⊢ (((𝑦 ∈ 𝑉 ∧ 𝑧 ∈ 𝑉) ∧ (𝑦 ≠ 𝑧 ∧ 𝑝 = {𝑦, 𝑧})) → (∀𝑣 ∈ 𝑉 ∀𝑛 ∈ (𝑉 ∖ {𝑣}){𝑛, 𝑣} ∈ 𝐸 → (𝐺 ∈ USGraph → 𝑝 ∈ 𝐸)))
39	38	ex 403	. . . . . . . 8 ⊢ ((𝑦 ∈ 𝑉 ∧ 𝑧 ∈ 𝑉) → ((𝑦 ≠ 𝑧 ∧ 𝑝 = {𝑦, 𝑧}) → (∀𝑣 ∈ 𝑉 ∀𝑛 ∈ (𝑉 ∖ {𝑣}){𝑛, 𝑣} ∈ 𝐸 → (𝐺 ∈ USGraph → 𝑝 ∈ 𝐸))))
40	39	rexlimivv 3245	. . . . . . 7 ⊢ (∃𝑦 ∈ 𝑉 ∃𝑧 ∈ 𝑉 (𝑦 ≠ 𝑧 ∧ 𝑝 = {𝑦, 𝑧}) → (∀𝑣 ∈ 𝑉 ∀𝑛 ∈ (𝑉 ∖ {𝑣}){𝑛, 𝑣} ∈ 𝐸 → (𝐺 ∈ USGraph → 𝑝 ∈ 𝐸)))
41	40	com13 88	. . . . . 6 ⊢ (𝐺 ∈ USGraph → (∀𝑣 ∈ 𝑉 ∀𝑛 ∈ (𝑉 ∖ {𝑣}){𝑛, 𝑣} ∈ 𝐸 → (∃𝑦 ∈ 𝑉 ∃𝑧 ∈ 𝑉 (𝑦 ≠ 𝑧 ∧ 𝑝 = {𝑦, 𝑧}) → 𝑝 ∈ 𝐸)))
42	41	imp 397	. . . . 5 ⊢ ((𝐺 ∈ USGraph ∧ ∀𝑣 ∈ 𝑉 ∀𝑛 ∈ (𝑉 ∖ {𝑣}){𝑛, 𝑣} ∈ 𝐸) → (∃𝑦 ∈ 𝑉 ∃𝑧 ∈ 𝑉 (𝑦 ≠ 𝑧 ∧ 𝑝 = {𝑦, 𝑧}) → 𝑝 ∈ 𝐸))
43	10, 42	syl5bi 234	. . . 4 ⊢ ((𝐺 ∈ USGraph ∧ ∀𝑣 ∈ 𝑉 ∀𝑛 ∈ (𝑉 ∖ {𝑣}){𝑛, 𝑣} ∈ 𝐸) → (𝑝 ∈ {𝑥 ∈ 𝒫 𝑉 ∣ (♯‘𝑥) = 2} → 𝑝 ∈ 𝐸))
44	43	ssrdv 3832	. . 3 ⊢ ((𝐺 ∈ USGraph ∧ ∀𝑣 ∈ 𝑉 ∀𝑛 ∈ (𝑉 ∖ {𝑣}){𝑛, 𝑣} ∈ 𝐸) → {𝑥 ∈ 𝒫 𝑉 ∣ (♯‘𝑥) = 2} ⊆ 𝐸)
45	9, 44	eqssd 3843	. 2 ⊢ ((𝐺 ∈ USGraph ∧ ∀𝑣 ∈ 𝑉 ∀𝑛 ∈ (𝑉 ∖ {𝑣}){𝑛, 𝑣} ∈ 𝐸) → 𝐸 = {𝑥 ∈ 𝒫 𝑉 ∣ (♯‘𝑥) = 2})
46	3, 45	sylbi 209	1 ⊢ (𝐺 ∈ ComplUSGraph → 𝐸 = {𝑥 ∈ 𝒫 𝑉 ∣ (♯‘𝑥) = 2})

Syntax hints:   → wi 4   ∧ wa 386   = wceq 1658   ∈ wcel 2166   ≠ wne 2998  ∀wral 3116  ∃wrex 3117  {crab 3120   ∖ cdif 3794   ⊆ wss 3797  𝒫 cpw 4377  {csn 4396  {cpr 4398  ‘cfv 6122  2c2 11405  ♯chash 13409  Vtxcvtx 26293  Edgcedg 26344  USGraphcusgr 26447  ComplUSGraphccusgr 26707

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1896  ax-4 1910  ax-5 2011  ax-6 2077  ax-7 2114  ax-8 2168  ax-9 2175  ax-10 2194  ax-11 2209  ax-12 2222  ax-13 2390  ax-ext 2802  ax-rep 4993  ax-sep 5004  ax-nul 5012  ax-pow 5064  ax-pr 5126  ax-un 7208  ax-cnex 10307  ax-resscn 10308  ax-1cn 10309  ax-icn 10310  ax-addcl 10311  ax-addrcl 10312  ax-mulcl 10313  ax-mulrcl 10314  ax-mulcom 10315  ax-addass 10316  ax-mulass 10317  ax-distr 10318  ax-i2m1 10319  ax-1ne0 10320  ax-1rid 10321  ax-rnegex 10322  ax-rrecex 10323  ax-cnre 10324  ax-pre-lttri 10325  ax-pre-lttrn 10326  ax-pre-ltadd 10327  ax-pre-mulgt0 10328

This theorem depends on definitions:  df-bi 199  df-an 387  df-or 881  df-3or 1114  df-3an 1115  df-tru 1662  df-fal 1672  df-ex 1881  df-nf 1885  df-sb 2070  df-mo 2604  df-eu 2639  df-clab 2811  df-cleq 2817  df-clel 2820  df-nfc 2957  df-ne 2999  df-nel 3102  df-ral 3121  df-rex 3122  df-reu 3123  df-rmo 3124  df-rab 3125  df-v 3415  df-sbc 3662  df-csb 3757  df-dif 3800  df-un 3802  df-in 3804  df-ss 3811  df-pss 3813  df-nul 4144  df-if 4306  df-pw 4379  df-sn 4397  df-pr 4399  df-tp 4401  df-op 4403  df-uni 4658  df-int 4697  df-iun 4741  df-br 4873  df-opab 4935  df-mpt 4952  df-tr 4975  df-id 5249  df-eprel 5254  df-po 5262  df-so 5263  df-fr 5300  df-we 5302  df-xp 5347  df-rel 5348  df-cnv 5349  df-co 5350  df-dm 5351  df-rn 5352  df-res 5353  df-ima 5354  df-pred 5919  df-ord 5965  df-on 5966  df-lim 5967  df-suc 5968  df-iota 6085  df-fun 6124  df-fn 6125  df-f 6126  df-f1 6127  df-fo 6128  df-f1o 6129  df-fv 6130  df-riota 6865  df-ov 6907  df-oprab 6908  df-mpt2 6909  df-om 7326  df-1st 7427  df-2nd 7428  df-wrecs 7671  df-recs 7733  df-rdg 7771  df-1o 7825  df-2o 7826  df-oadd 7829  df-er 8008  df-en 8222  df-dom 8223  df-sdom 8224  df-fin 8225  df-card 9077  df-cda 9304  df-pnf 10392  df-mnf 10393  df-xr 10394  df-ltxr 10395  df-le 10396  df-sub 10586  df-neg 10587  df-nn 11350  df-2 11413  df-n0 11618  df-xnn0 11690  df-z 11704  df-uz 11968  df-fz 12619  df-hash 13410  df-edg 26345  df-upgr 26379  df-umgr 26380  df-usgr 26449  df-nbgr 26629  df-uvtx 26683  df-cplgr 26708  df-cusgr 26709

This theorem is referenced by:  cusgrfilem1  26752