Theorem uspgredg2v 16265

Description: In a simple pseudograph, the mapping of edges having a fixed endpoint to the "other" vertex of the edge (which may be the fixed vertex itself in the case of a loop) is a one-to-one function into the set of vertices. (Contributed by Alexander van der Vekens, 4-Jan-2018.) (Revised by AV, 6-Dec-2020.)

Hypotheses

Ref	Expression
uspgredg2v.v	|- V = (Vtx ` G )
uspgredg2v.e	|- E = (Edg ` G )
uspgredg2v.a	|- A = { e e. E | N e. e }
uspgredg2v.f	|- F = ( y e. A |-> ( iota_ z e. V y = { N , z } ) )

Assertion

Ref	Expression
uspgredg2v	|- ( ( G e. USPGraph /\ N e. V ) -> F : A -1-1-> V )

Distinct variable groups:   e, E   z, G   e, N   z, N   z, V   y, A   y, G   y, N, z   y, V   y, e

Allowed substitution hints:   A( z, e)   E( y, z)   F( y, z, e)   G( e)   V( e)

Proof of Theorem uspgredg2v

Dummy variables x n are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		uspgredg2v.v	. . . . 5 |- V = (Vtx ` G )
2		uspgredg2v.e	. . . . 5 |- E = (Edg ` G )
3		uspgredg2v.a	. . . . 5 |- A = { e e. E | N e. e }
4	1, 2, 3	uspgredg2vlem 16264	. . . 4 |- ( ( G e. USPGraph /\ y e. A ) -> ( iota_ z e. V y = { N , z } ) e. V )
5	4	ralrimiva 2617	. . 3 |- ( G e. USPGraph -> A. y e. A ( iota_ z e. V y = { N , z } ) e. V )
6	5	adantr 276	. 2 |- ( ( G e. USPGraph /\ N e. V ) -> A. y e. A ( iota_ z e. V y = { N , z } ) e. V )
7		preq2 3771	. . . . . . 7 |- ( z = n -> { N , z } = { N , n } )
8	7	eqeq2d 2246	. . . . . 6 |- ( z = n -> ( y = { N , z } <-> y = { N , n } ) )
9	8	cbvriotavw 6016	. . . . 5 |- ( iota_ z e. V y = { N , z } ) = ( iota_ n e. V y = { N , n } )
10	7	eqeq2d 2246	. . . . . 6 |- ( z = n -> ( x = { N , z } <-> x = { N , n } ) )
11	10	cbvriotavw 6016	. . . . 5 |- ( iota_ z e. V x = { N , z } ) = ( iota_ n e. V x = { N , n } )
12		simpl 109	. . . . . . . 8 |- ( ( G e. USPGraph /\ N e. V ) -> G e. USPGraph )
13		eleq2w 2296	. . . . . . . . . . 11 |- ( e = y -> ( N e. e <-> N e. y ) )
14	13, 3	elrab2 2978	. . . . . . . . . 10 |- ( y e. A <-> ( y e. E /\ N e. y ) )
15	2	eleq2i 2301	. . . . . . . . . . . 12 |- ( y e. E <-> y e. (Edg ` G ) )
16	15	biimpi 120	. . . . . . . . . . 11 |- ( y e. E -> y e. (Edg ` G ) )
17	16	anim1i 340	. . . . . . . . . 10 |- ( ( y e. E /\ N e. y ) -> ( y e. (Edg ` G ) /\ N e. y ) )
18	14, 17	sylbi 121	. . . . . . . . 9 |- ( y e. A -> ( y e. (Edg ` G ) /\ N e. y ) )
19	18	adantr 276	. . . . . . . 8 |- ( ( y e. A /\ x e. A ) -> ( y e. (Edg ` G ) /\ N e. y ) )
20	12, 19	anim12i 338	. . . . . . 7 |- ( ( ( G e. USPGraph /\ N e. V ) /\ ( y e. A /\ x e. A ) ) -> ( G e. USPGraph /\ ( y e. (Edg ` G ) /\ N e. y ) ) )
21		3anass 1009	. . . . . . 7 |- ( ( G e. USPGraph /\ y e. (Edg ` G ) /\ N e. y ) <-> ( G e. USPGraph /\ ( y e. (Edg ` G ) /\ N e. y ) ) )
22	20, 21	sylibr 134	. . . . . 6 |- ( ( ( G e. USPGraph /\ N e. V ) /\ ( y e. A /\ x e. A ) ) -> ( G e. USPGraph /\ y e. (Edg ` G ) /\ N e. y ) )
23		uspgredg2vtxeu 16262	. . . . . . 7 |- ( ( G e. USPGraph /\ y e. (Edg ` G ) /\ N e. y ) -> E! n e. (Vtx ` G ) y = { N , n } )
24		reueq1 2745	. . . . . . . 8 |- ( V = (Vtx ` G ) -> ( E! n e. V y = { N , n } <-> E! n e. (Vtx ` G ) y = { N , n } ) )
25	1, 24	ax-mp 5	. . . . . . 7 |- ( E! n e. V y = { N , n } <-> E! n e. (Vtx ` G ) y = { N , n } )
26	23, 25	sylibr 134	. . . . . 6 |- ( ( G e. USPGraph /\ y e. (Edg ` G ) /\ N e. y ) -> E! n e. V y = { N , n } )
27	22, 26	syl 14	. . . . 5 |- ( ( ( G e. USPGraph /\ N e. V ) /\ ( y e. A /\ x e. A ) ) -> E! n e. V y = { N , n } )
28		eleq2w 2296	. . . . . . . . . . 11 |- ( e = x -> ( N e. e <-> N e. x ) )
29	28, 3	elrab2 2978	. . . . . . . . . 10 |- ( x e. A <-> ( x e. E /\ N e. x ) )
30	2	eleq2i 2301	. . . . . . . . . . . 12 |- ( x e. E <-> x e. (Edg ` G ) )
31	30	biimpi 120	. . . . . . . . . . 11 |- ( x e. E -> x e. (Edg ` G ) )
32	31	anim1i 340	. . . . . . . . . 10 |- ( ( x e. E /\ N e. x ) -> ( x e. (Edg ` G ) /\ N e. x ) )
33	29, 32	sylbi 121	. . . . . . . . 9 |- ( x e. A -> ( x e. (Edg ` G ) /\ N e. x ) )
34	33	adantl 277	. . . . . . . 8 |- ( ( y e. A /\ x e. A ) -> ( x e. (Edg ` G ) /\ N e. x ) )
35	12, 34	anim12i 338	. . . . . . 7 |- ( ( ( G e. USPGraph /\ N e. V ) /\ ( y e. A /\ x e. A ) ) -> ( G e. USPGraph /\ ( x e. (Edg ` G ) /\ N e. x ) ) )
36		3anass 1009	. . . . . . 7 |- ( ( G e. USPGraph /\ x e. (Edg ` G ) /\ N e. x ) <-> ( G e. USPGraph /\ ( x e. (Edg ` G ) /\ N e. x ) ) )
37	35, 36	sylibr 134	. . . . . 6 |- ( ( ( G e. USPGraph /\ N e. V ) /\ ( y e. A /\ x e. A ) ) -> ( G e. USPGraph /\ x e. (Edg ` G ) /\ N e. x ) )
38		uspgredg2vtxeu 16262	. . . . . . 7 |- ( ( G e. USPGraph /\ x e. (Edg ` G ) /\ N e. x ) -> E! n e. (Vtx ` G ) x = { N , n } )
39		reueq1 2745	. . . . . . . 8 |- ( V = (Vtx ` G ) -> ( E! n e. V x = { N , n } <-> E! n e. (Vtx ` G ) x = { N , n } ) )
40	1, 39	ax-mp 5	. . . . . . 7 |- ( E! n e. V x = { N , n } <-> E! n e. (Vtx ` G ) x = { N , n } )
41	38, 40	sylibr 134	. . . . . 6 |- ( ( G e. USPGraph /\ x e. (Edg ` G ) /\ N e. x ) -> E! n e. V x = { N , n } )
42	37, 41	syl 14	. . . . 5 |- ( ( ( G e. USPGraph /\ N e. V ) /\ ( y e. A /\ x e. A ) ) -> E! n e. V x = { N , n } )
43	9, 11, 27, 42	riotaeqimp 6030	. . . 4 |- ( ( ( ( G e. USPGraph /\ N e. V ) /\ ( y e. A /\ x e. A ) ) /\ ( iota_ z e. V y = { N , z } ) = ( iota_ z e. V x = { N , z } ) ) -> y = x )
44	43	ex 115	. . 3 |- ( ( ( G e. USPGraph /\ N e. V ) /\ ( y e. A /\ x e. A ) ) -> ( ( iota_ z e. V y = { N , z } ) = ( iota_ z e. V x = { N , z } ) -> y = x ) )
45	44	ralrimivva 2626	. 2 |- ( ( G e. USPGraph /\ N e. V ) -> A. y e. A A. x e. A ( ( iota_ z e. V y = { N , z } ) = ( iota_ z e. V x = { N , z } ) -> y = x ) )
46		uspgredg2v.f	. . 3 |- F = ( y e. A |-> ( iota_ z e. V y = { N , z } ) )
47		eqeq1 2241	. . . 4 |- ( y = x -> ( y = { N , z } <-> x = { N , z } ) )
48	47	riotabidv 6007	. . 3 |- ( y = x -> ( iota_ z e. V y = { N , z } ) = ( iota_ z e. V x = { N , z } ) )
49	46, 48	f1mpt 5946	. 2 |- ( F : A -1-1-> V <-> ( A. y e. A ( iota_ z e. V y = { N , z } ) e. V /\ A. y e. A A. x e. A ( ( iota_ z e. V y = { N , z } ) = ( iota_ z e. V x = { N , z } ) -> y = x ) ) )
50	6, 45, 49	sylanbrc 417	1 |- ( ( G e. USPGraph /\ N e. V ) -> F : A -1-1-> V )

Syntax hints:   -> wi 4   /\ wa 104   <-> wb 105   /\ w3a 1005   = wceq 1398   e. wcel 2205   A.wral 2522   E!wreu 2524   {crab 2526   {cpr 3692   |-> cmpt 4173   -1-1->wf1 5351   ` cfv 5354   iota_crio 6004  Vtxcvtx 16056  Edgcedg 16101  USPGraphcuspgr 16197

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-in1 619  ax-in2 620  ax-io 717  ax-5 1496  ax-7 1497  ax-gen 1498  ax-ie1 1542  ax-ie2 1543  ax-8 1553  ax-10 1554  ax-11 1555  ax-i12 1556  ax-bndl 1558  ax-4 1559  ax-17 1575  ax-i9 1579  ax-ial 1583  ax-i5r 1584  ax-13 2207  ax-14 2208  ax-ext 2216  ax-sep 4230  ax-nul 4238  ax-pow 4289  ax-pr 4324  ax-un 4556  ax-setind 4661  ax-cnex 8223  ax-resscn 8224  ax-1cn 8225  ax-1re 8226  ax-icn 8227  ax-addcl 8228  ax-addrcl 8229  ax-mulcl 8230  ax-addcom 8232  ax-mulcom 8233  ax-addass 8234  ax-mulass 8235  ax-distr 8236  ax-i2m1 8237  ax-1rid 8239  ax-0id 8240  ax-rnegex 8241  ax-cnre 8243

This theorem depends on definitions:  df-bi 117  df-3an 1007  df-tru 1401  df-fal 1404  df-nf 1510  df-sb 1812  df-eu 2085  df-mo 2086  df-clab 2221  df-cleq 2227  df-clel 2230  df-nfc 2375  df-ne 2415  df-ral 2527  df-rex 2528  df-reu 2529  df-rmo 2530  df-rab 2531  df-v 2817  df-sbc 3045  df-csb 3141  df-dif 3215  df-un 3217  df-in 3219  df-ss 3226  df-nul 3511  df-if 3623  df-pw 3673  df-sn 3697  df-pr 3698  df-op 3700  df-uni 3917  df-int 3952  df-br 4112  df-opab 4174  df-mpt 4175  df-tr 4211  df-id 4416  df-iord 4489  df-on 4491  df-suc 4494  df-xp 4757  df-rel 4758  df-cnv 4759  df-co 4760  df-dm 4761  df-rn 4762  df-res 4763  df-ima 4764  df-iota 5314  df-fun 5356  df-fn 5357  df-f 5358  df-f1 5359  df-fo 5360  df-f1o 5361  df-fv 5362  df-riota 6005  df-ov 6055  df-oprab 6056  df-mpo 6057  df-1st 6336  df-2nd 6337  df-1o 6649  df-2o 6650  df-en 6978  df-sub 8451  df-inn 9243  df-2 9301  df-3 9302  df-4 9303  df-5 9304  df-6 9305  df-7 9306  df-8 9307  df-9 9308  df-n0 9502  df-dec 9716  df-ndx 13236  df-slot 13237  df-base 13239  df-edgf 16049  df-vtx 16058  df-iedg 16059  df-edg 16102  df-upgren 16137  df-uspgren 16199

This theorem is referenced by:  uspgredgdomord  16273