Metamath Proof Explorer


Theorem usgruspgrb

Description: A class is a simple graph iff it is a simple pseudograph without loops. (Contributed by AV, 18-Oct-2020)

Ref Expression
Assertion usgruspgrb G USGraph G USHGraph e Edg G e = 2

Proof

Step Hyp Ref Expression
1 usgruspgr G USGraph G USHGraph
2 edgusgr G USGraph e Edg G e 𝒫 Vtx G e = 2
3 2 simprd G USGraph e Edg G e = 2
4 3 ralrimiva G USGraph e Edg G e = 2
5 1 4 jca G USGraph G USHGraph e Edg G e = 2
6 edgval Edg G = ran iEdg G
7 6 a1i G USHGraph Edg G = ran iEdg G
8 7 raleqdv G USHGraph e Edg G e = 2 e ran iEdg G e = 2
9 eqid Vtx G = Vtx G
10 eqid iEdg G = iEdg G
11 9 10 uspgrf G USHGraph iEdg G : dom iEdg G 1-1 x 𝒫 Vtx G | x 2
12 f1f iEdg G : dom iEdg G 1-1 x 𝒫 Vtx G | x 2 iEdg G : dom iEdg G x 𝒫 Vtx G | x 2
13 12 frnd iEdg G : dom iEdg G 1-1 x 𝒫 Vtx G | x 2 ran iEdg G x 𝒫 Vtx G | x 2
14 ssel2 ran iEdg G x 𝒫 Vtx G | x 2 y ran iEdg G y x 𝒫 Vtx G | x 2
15 14 expcom y ran iEdg G ran iEdg G x 𝒫 Vtx G | x 2 y x 𝒫 Vtx G | x 2
16 fveqeq2 e = y e = 2 y = 2
17 16 rspcv y ran iEdg G e ran iEdg G e = 2 y = 2
18 fveq2 x = y x = y
19 18 breq1d x = y x 2 y 2
20 19 elrab y x 𝒫 Vtx G | x 2 y 𝒫 Vtx G y 2
21 eldifi y 𝒫 Vtx G y 𝒫 Vtx G
22 21 anim1i y 𝒫 Vtx G y = 2 y 𝒫 Vtx G y = 2
23 fveqeq2 x = y x = 2 y = 2
24 23 elrab y x 𝒫 Vtx G | x = 2 y 𝒫 Vtx G y = 2
25 22 24 sylibr y 𝒫 Vtx G y = 2 y x 𝒫 Vtx G | x = 2
26 25 ex y 𝒫 Vtx G y = 2 y x 𝒫 Vtx G | x = 2
27 26 adantr y 𝒫 Vtx G y 2 y = 2 y x 𝒫 Vtx G | x = 2
28 20 27 sylbi y x 𝒫 Vtx G | x 2 y = 2 y x 𝒫 Vtx G | x = 2
29 17 28 syl9 y ran iEdg G y x 𝒫 Vtx G | x 2 e ran iEdg G e = 2 y x 𝒫 Vtx G | x = 2
30 15 29 syld y ran iEdg G ran iEdg G x 𝒫 Vtx G | x 2 e ran iEdg G e = 2 y x 𝒫 Vtx G | x = 2
31 30 com13 e ran iEdg G e = 2 ran iEdg G x 𝒫 Vtx G | x 2 y ran iEdg G y x 𝒫 Vtx G | x = 2
32 31 imp e ran iEdg G e = 2 ran iEdg G x 𝒫 Vtx G | x 2 y ran iEdg G y x 𝒫 Vtx G | x = 2
33 32 ssrdv e ran iEdg G e = 2 ran iEdg G x 𝒫 Vtx G | x 2 ran iEdg G x 𝒫 Vtx G | x = 2
34 33 ex e ran iEdg G e = 2 ran iEdg G x 𝒫 Vtx G | x 2 ran iEdg G x 𝒫 Vtx G | x = 2
35 13 34 mpan9 iEdg G : dom iEdg G 1-1 x 𝒫 Vtx G | x 2 e ran iEdg G e = 2 ran iEdg G x 𝒫 Vtx G | x = 2
36 f1ssr iEdg G : dom iEdg G 1-1 x 𝒫 Vtx G | x 2 ran iEdg G x 𝒫 Vtx G | x = 2 iEdg G : dom iEdg G 1-1 x 𝒫 Vtx G | x = 2
37 35 36 syldan iEdg G : dom iEdg G 1-1 x 𝒫 Vtx G | x 2 e ran iEdg G e = 2 iEdg G : dom iEdg G 1-1 x 𝒫 Vtx G | x = 2
38 37 ex iEdg G : dom iEdg G 1-1 x 𝒫 Vtx G | x 2 e ran iEdg G e = 2 iEdg G : dom iEdg G 1-1 x 𝒫 Vtx G | x = 2
39 11 38 syl G USHGraph e ran iEdg G e = 2 iEdg G : dom iEdg G 1-1 x 𝒫 Vtx G | x = 2
40 8 39 sylbid G USHGraph e Edg G e = 2 iEdg G : dom iEdg G 1-1 x 𝒫 Vtx G | x = 2
41 40 imp G USHGraph e Edg G e = 2 iEdg G : dom iEdg G 1-1 x 𝒫 Vtx G | x = 2
42 9 10 isusgrs G USHGraph G USGraph iEdg G : dom iEdg G 1-1 x 𝒫 Vtx G | x = 2
43 42 adantr G USHGraph e Edg G e = 2 G USGraph iEdg G : dom iEdg G 1-1 x 𝒫 Vtx G | x = 2
44 41 43 mpbird G USHGraph e Edg G e = 2 G USGraph
45 5 44 impbii G USGraph G USHGraph e Edg G e = 2