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Theorem usgr2pth0 26661
Description: In a simply graph, there is a path of length 2 iff there are three distinct vertices so that one of them is connected to each of the two others by an edge. (Contributed by Alexander van der Vekens, 27-Jan-2018.) (Revised by AV, 5-Jun-2021.)
Hypotheses
Ref Expression
usgr2pthlem.v  |-  V  =  (Vtx `  G )
usgr2pthlem.i  |-  I  =  (iEdg `  G )
Assertion
Ref Expression
usgr2pth0  |-  ( G  e. USGraph  ->  ( ( F (Paths `  G ) P  /\  ( # `  F
)  =  2 )  <-> 
( F : ( 0..^ 2 ) -1-1-> dom  I  /\  P : ( 0 ... 2 )
-1-1-> V  /\  E. x  e.  V  E. y  e.  ( V  \  {
x } ) E. z  e.  ( V 
\  { x ,  y } ) ( ( ( P ` 
0 )  =  x  /\  ( P ` 
1 )  =  z  /\  ( P ` 
2 )  =  y )  /\  ( ( I `  ( F `
 0 ) )  =  { x ,  z }  /\  (
I `  ( F `  1 ) )  =  { z ,  y } ) ) ) ) )
Distinct variable groups:    x, F, y, z    x, G, y, z    x, I, y, z    x, P, y, z    x, V, y, z

Proof of Theorem usgr2pth0
StepHypRef Expression
1 usgr2pthlem.v . . 3  |-  V  =  (Vtx `  G )
2 usgr2pthlem.i . . 3  |-  I  =  (iEdg `  G )
31, 2usgr2pth 26660 . 2  |-  ( G  e. USGraph  ->  ( ( F (Paths `  G ) P  /\  ( # `  F
)  =  2 )  <-> 
( F : ( 0..^ 2 ) -1-1-> dom  I  /\  P : ( 0 ... 2 )
-1-1-> V  /\  E. x  e.  V  E. z  e.  ( V  \  {
x } ) E. y  e.  ( V 
\  { x ,  z } ) ( ( ( P ` 
0 )  =  x  /\  ( P ` 
1 )  =  z  /\  ( P ` 
2 )  =  y )  /\  ( ( I `  ( F `
 0 ) )  =  { x ,  z }  /\  (
I `  ( F `  1 ) )  =  { z ,  y } ) ) ) ) )
4 r19.42v 3092 . . . . . . . . 9  |-  ( E. y  e.  ( V 
\  { x ,  z } ) ( z  =/=  x  /\  ( ( ( P `
 0 )  =  x  /\  ( P `
 1 )  =  z  /\  ( P `
 2 )  =  y )  /\  (
( I `  ( F `  0 )
)  =  { x ,  z }  /\  ( I `  ( F `  1 )
)  =  { z ,  y } ) ) )  <->  ( z  =/=  x  /\  E. y  e.  ( V  \  {
x ,  z } ) ( ( ( P `  0 )  =  x  /\  ( P `  1 )  =  z  /\  ( P `  2 )  =  y )  /\  ( ( I `  ( F `  0 ) )  =  { x ,  z }  /\  ( I `  ( F `  1 )
)  =  { z ,  y } ) ) ) )
5 rexdifpr 4205 . . . . . . . . 9  |-  ( E. y  e.  ( V 
\  { x ,  z } ) ( z  =/=  x  /\  ( ( ( P `
 0 )  =  x  /\  ( P `
 1 )  =  z  /\  ( P `
 2 )  =  y )  /\  (
( I `  ( F `  0 )
)  =  { x ,  z }  /\  ( I `  ( F `  1 )
)  =  { z ,  y } ) ) )  <->  E. y  e.  V  ( y  =/=  x  /\  y  =/=  z  /\  ( z  =/=  x  /\  (
( ( P ` 
0 )  =  x  /\  ( P ` 
1 )  =  z  /\  ( P ` 
2 )  =  y )  /\  ( ( I `  ( F `
 0 ) )  =  { x ,  z }  /\  (
I `  ( F `  1 ) )  =  { z ,  y } ) ) ) ) )
64, 5bitr3i 266 . . . . . . . 8  |-  ( ( z  =/=  x  /\  E. y  e.  ( V 
\  { x ,  z } ) ( ( ( P ` 
0 )  =  x  /\  ( P ` 
1 )  =  z  /\  ( P ` 
2 )  =  y )  /\  ( ( I `  ( F `
 0 ) )  =  { x ,  z }  /\  (
I `  ( F `  1 ) )  =  { z ,  y } ) ) )  <->  E. y  e.  V  ( y  =/=  x  /\  y  =/=  z  /\  ( z  =/=  x  /\  ( ( ( P `
 0 )  =  x  /\  ( P `
 1 )  =  z  /\  ( P `
 2 )  =  y )  /\  (
( I `  ( F `  0 )
)  =  { x ,  z }  /\  ( I `  ( F `  1 )
)  =  { z ,  y } ) ) ) ) )
76rexbii 3041 . . . . . . 7  |-  ( E. z  e.  V  ( z  =/=  x  /\  E. y  e.  ( V 
\  { x ,  z } ) ( ( ( P ` 
0 )  =  x  /\  ( P ` 
1 )  =  z  /\  ( P ` 
2 )  =  y )  /\  ( ( I `  ( F `
 0 ) )  =  { x ,  z }  /\  (
I `  ( F `  1 ) )  =  { z ,  y } ) ) )  <->  E. z  e.  V  E. y  e.  V  ( y  =/=  x  /\  y  =/=  z  /\  ( z  =/=  x  /\  ( ( ( P `
 0 )  =  x  /\  ( P `
 1 )  =  z  /\  ( P `
 2 )  =  y )  /\  (
( I `  ( F `  0 )
)  =  { x ,  z }  /\  ( I `  ( F `  1 )
)  =  { z ,  y } ) ) ) ) )
8 rexcom 3099 . . . . . . 7  |-  ( E. z  e.  V  E. y  e.  V  (
y  =/=  x  /\  y  =/=  z  /\  (
z  =/=  x  /\  ( ( ( P `
 0 )  =  x  /\  ( P `
 1 )  =  z  /\  ( P `
 2 )  =  y )  /\  (
( I `  ( F `  0 )
)  =  { x ,  z }  /\  ( I `  ( F `  1 )
)  =  { z ,  y } ) ) ) )  <->  E. y  e.  V  E. z  e.  V  ( y  =/=  x  /\  y  =/=  z  /\  ( z  =/=  x  /\  (
( ( P ` 
0 )  =  x  /\  ( P ` 
1 )  =  z  /\  ( P ` 
2 )  =  y )  /\  ( ( I `  ( F `
 0 ) )  =  { x ,  z }  /\  (
I `  ( F `  1 ) )  =  { z ,  y } ) ) ) ) )
9 df-3an 1039 . . . . . . . . . . 11  |-  ( ( y  =/=  x  /\  y  =/=  z  /\  (
z  =/=  x  /\  ( ( ( P `
 0 )  =  x  /\  ( P `
 1 )  =  z  /\  ( P `
 2 )  =  y )  /\  (
( I `  ( F `  0 )
)  =  { x ,  z }  /\  ( I `  ( F `  1 )
)  =  { z ,  y } ) ) ) )  <->  ( (
y  =/=  x  /\  y  =/=  z )  /\  ( z  =/=  x  /\  ( ( ( P `
 0 )  =  x  /\  ( P `
 1 )  =  z  /\  ( P `
 2 )  =  y )  /\  (
( I `  ( F `  0 )
)  =  { x ,  z }  /\  ( I `  ( F `  1 )
)  =  { z ,  y } ) ) ) ) )
10 anass 681 . . . . . . . . . . 11  |-  ( ( ( ( y  =/=  x  /\  y  =/=  z )  /\  z  =/=  x )  /\  (
( ( P ` 
0 )  =  x  /\  ( P ` 
1 )  =  z  /\  ( P ` 
2 )  =  y )  /\  ( ( I `  ( F `
 0 ) )  =  { x ,  z }  /\  (
I `  ( F `  1 ) )  =  { z ,  y } ) ) )  <->  ( ( y  =/=  x  /\  y  =/=  z )  /\  (
z  =/=  x  /\  ( ( ( P `
 0 )  =  x  /\  ( P `
 1 )  =  z  /\  ( P `
 2 )  =  y )  /\  (
( I `  ( F `  0 )
)  =  { x ,  z }  /\  ( I `  ( F `  1 )
)  =  { z ,  y } ) ) ) ) )
11 anass 681 . . . . . . . . . . . 12  |-  ( ( ( ( z  =/=  x  /\  z  =/=  y )  /\  y  =/=  x )  /\  (
( ( P ` 
0 )  =  x  /\  ( P ` 
1 )  =  z  /\  ( P ` 
2 )  =  y )  /\  ( ( I `  ( F `
 0 ) )  =  { x ,  z }  /\  (
I `  ( F `  1 ) )  =  { z ,  y } ) ) )  <->  ( ( z  =/=  x  /\  z  =/=  y )  /\  (
y  =/=  x  /\  ( ( ( P `
 0 )  =  x  /\  ( P `
 1 )  =  z  /\  ( P `
 2 )  =  y )  /\  (
( I `  ( F `  0 )
)  =  { x ,  z }  /\  ( I `  ( F `  1 )
)  =  { z ,  y } ) ) ) ) )
12 anass 681 . . . . . . . . . . . . . 14  |-  ( ( ( y  =/=  x  /\  y  =/=  z
)  /\  z  =/=  x )  <->  ( y  =/=  x  /\  ( y  =/=  z  /\  z  =/=  x ) ) )
13 ancom 466 . . . . . . . . . . . . . 14  |-  ( ( y  =/=  x  /\  ( y  =/=  z  /\  z  =/=  x
) )  <->  ( (
y  =/=  z  /\  z  =/=  x )  /\  y  =/=  x ) )
14 necom 2847 . . . . . . . . . . . . . . . 16  |-  ( y  =/=  z  <->  z  =/=  y )
1514anbi2ci 732 . . . . . . . . . . . . . . 15  |-  ( ( y  =/=  z  /\  z  =/=  x )  <->  ( z  =/=  x  /\  z  =/=  y ) )
1615anbi1i 731 . . . . . . . . . . . . . 14  |-  ( ( ( y  =/=  z  /\  z  =/=  x
)  /\  y  =/=  x )  <->  ( (
z  =/=  x  /\  z  =/=  y )  /\  y  =/=  x ) )
1712, 13, 163bitri 286 . . . . . . . . . . . . 13  |-  ( ( ( y  =/=  x  /\  y  =/=  z
)  /\  z  =/=  x )  <->  ( (
z  =/=  x  /\  z  =/=  y )  /\  y  =/=  x ) )
1817anbi1i 731 . . . . . . . . . . . 12  |-  ( ( ( ( y  =/=  x  /\  y  =/=  z )  /\  z  =/=  x )  /\  (
( ( P ` 
0 )  =  x  /\  ( P ` 
1 )  =  z  /\  ( P ` 
2 )  =  y )  /\  ( ( I `  ( F `
 0 ) )  =  { x ,  z }  /\  (
I `  ( F `  1 ) )  =  { z ,  y } ) ) )  <->  ( ( ( z  =/=  x  /\  z  =/=  y )  /\  y  =/=  x )  /\  ( ( ( P `
 0 )  =  x  /\  ( P `
 1 )  =  z  /\  ( P `
 2 )  =  y )  /\  (
( I `  ( F `  0 )
)  =  { x ,  z }  /\  ( I `  ( F `  1 )
)  =  { z ,  y } ) ) ) )
19 df-3an 1039 . . . . . . . . . . . 12  |-  ( ( z  =/=  x  /\  z  =/=  y  /\  (
y  =/=  x  /\  ( ( ( P `
 0 )  =  x  /\  ( P `
 1 )  =  z  /\  ( P `
 2 )  =  y )  /\  (
( I `  ( F `  0 )
)  =  { x ,  z }  /\  ( I `  ( F `  1 )
)  =  { z ,  y } ) ) ) )  <->  ( (
z  =/=  x  /\  z  =/=  y )  /\  ( y  =/=  x  /\  ( ( ( P `
 0 )  =  x  /\  ( P `
 1 )  =  z  /\  ( P `
 2 )  =  y )  /\  (
( I `  ( F `  0 )
)  =  { x ,  z }  /\  ( I `  ( F `  1 )
)  =  { z ,  y } ) ) ) ) )
2011, 18, 193bitr4i 292 . . . . . . . . . . 11  |-  ( ( ( ( y  =/=  x  /\  y  =/=  z )  /\  z  =/=  x )  /\  (
( ( P ` 
0 )  =  x  /\  ( P ` 
1 )  =  z  /\  ( P ` 
2 )  =  y )  /\  ( ( I `  ( F `
 0 ) )  =  { x ,  z }  /\  (
I `  ( F `  1 ) )  =  { z ,  y } ) ) )  <->  ( z  =/=  x  /\  z  =/=  y  /\  ( y  =/=  x  /\  (
( ( P ` 
0 )  =  x  /\  ( P ` 
1 )  =  z  /\  ( P ` 
2 )  =  y )  /\  ( ( I `  ( F `
 0 ) )  =  { x ,  z }  /\  (
I `  ( F `  1 ) )  =  { z ,  y } ) ) ) ) )
219, 10, 203bitr2i 288 . . . . . . . . . 10  |-  ( ( y  =/=  x  /\  y  =/=  z  /\  (
z  =/=  x  /\  ( ( ( P `
 0 )  =  x  /\  ( P `
 1 )  =  z  /\  ( P `
 2 )  =  y )  /\  (
( I `  ( F `  0 )
)  =  { x ,  z }  /\  ( I `  ( F `  1 )
)  =  { z ,  y } ) ) ) )  <->  ( z  =/=  x  /\  z  =/=  y  /\  ( y  =/=  x  /\  (
( ( P ` 
0 )  =  x  /\  ( P ` 
1 )  =  z  /\  ( P ` 
2 )  =  y )  /\  ( ( I `  ( F `
 0 ) )  =  { x ,  z }  /\  (
I `  ( F `  1 ) )  =  { z ,  y } ) ) ) ) )
2221rexbii 3041 . . . . . . . . 9  |-  ( E. z  e.  V  ( y  =/=  x  /\  y  =/=  z  /\  (
z  =/=  x  /\  ( ( ( P `
 0 )  =  x  /\  ( P `
 1 )  =  z  /\  ( P `
 2 )  =  y )  /\  (
( I `  ( F `  0 )
)  =  { x ,  z }  /\  ( I `  ( F `  1 )
)  =  { z ,  y } ) ) ) )  <->  E. z  e.  V  ( z  =/=  x  /\  z  =/=  y  /\  ( y  =/=  x  /\  (
( ( P ` 
0 )  =  x  /\  ( P ` 
1 )  =  z  /\  ( P ` 
2 )  =  y )  /\  ( ( I `  ( F `
 0 ) )  =  { x ,  z }  /\  (
I `  ( F `  1 ) )  =  { z ,  y } ) ) ) ) )
23 rexdifpr 4205 . . . . . . . . 9  |-  ( E. z  e.  ( V 
\  { x ,  y } ) ( y  =/=  x  /\  ( ( ( P `
 0 )  =  x  /\  ( P `
 1 )  =  z  /\  ( P `
 2 )  =  y )  /\  (
( I `  ( F `  0 )
)  =  { x ,  z }  /\  ( I `  ( F `  1 )
)  =  { z ,  y } ) ) )  <->  E. z  e.  V  ( z  =/=  x  /\  z  =/=  y  /\  ( y  =/=  x  /\  (
( ( P ` 
0 )  =  x  /\  ( P ` 
1 )  =  z  /\  ( P ` 
2 )  =  y )  /\  ( ( I `  ( F `
 0 ) )  =  { x ,  z }  /\  (
I `  ( F `  1 ) )  =  { z ,  y } ) ) ) ) )
24 r19.42v 3092 . . . . . . . . 9  |-  ( E. z  e.  ( V 
\  { x ,  y } ) ( y  =/=  x  /\  ( ( ( P `
 0 )  =  x  /\  ( P `
 1 )  =  z  /\  ( P `
 2 )  =  y )  /\  (
( I `  ( F `  0 )
)  =  { x ,  z }  /\  ( I `  ( F `  1 )
)  =  { z ,  y } ) ) )  <->  ( y  =/=  x  /\  E. z  e.  ( V  \  {
x ,  y } ) ( ( ( P `  0 )  =  x  /\  ( P `  1 )  =  z  /\  ( P `  2 )  =  y )  /\  ( ( I `  ( F `  0 ) )  =  { x ,  z }  /\  ( I `  ( F `  1 )
)  =  { z ,  y } ) ) ) )
2522, 23, 243bitr2i 288 . . . . . . . 8  |-  ( E. z  e.  V  ( y  =/=  x  /\  y  =/=  z  /\  (
z  =/=  x  /\  ( ( ( P `
 0 )  =  x  /\  ( P `
 1 )  =  z  /\  ( P `
 2 )  =  y )  /\  (
( I `  ( F `  0 )
)  =  { x ,  z }  /\  ( I `  ( F `  1 )
)  =  { z ,  y } ) ) ) )  <->  ( y  =/=  x  /\  E. z  e.  ( V  \  {
x ,  y } ) ( ( ( P `  0 )  =  x  /\  ( P `  1 )  =  z  /\  ( P `  2 )  =  y )  /\  ( ( I `  ( F `  0 ) )  =  { x ,  z }  /\  ( I `  ( F `  1 )
)  =  { z ,  y } ) ) ) )
2625rexbii 3041 . . . . . . 7  |-  ( E. y  e.  V  E. z  e.  V  (
y  =/=  x  /\  y  =/=  z  /\  (
z  =/=  x  /\  ( ( ( P `
 0 )  =  x  /\  ( P `
 1 )  =  z  /\  ( P `
 2 )  =  y )  /\  (
( I `  ( F `  0 )
)  =  { x ,  z }  /\  ( I `  ( F `  1 )
)  =  { z ,  y } ) ) ) )  <->  E. y  e.  V  ( y  =/=  x  /\  E. z  e.  ( V  \  {
x ,  y } ) ( ( ( P `  0 )  =  x  /\  ( P `  1 )  =  z  /\  ( P `  2 )  =  y )  /\  ( ( I `  ( F `  0 ) )  =  { x ,  z }  /\  ( I `  ( F `  1 )
)  =  { z ,  y } ) ) ) )
277, 8, 263bitri 286 . . . . . 6  |-  ( E. z  e.  V  ( z  =/=  x  /\  E. y  e.  ( V 
\  { x ,  z } ) ( ( ( P ` 
0 )  =  x  /\  ( P ` 
1 )  =  z  /\  ( P ` 
2 )  =  y )  /\  ( ( I `  ( F `
 0 ) )  =  { x ,  z }  /\  (
I `  ( F `  1 ) )  =  { z ,  y } ) ) )  <->  E. y  e.  V  ( y  =/=  x  /\  E. z  e.  ( V  \  { x ,  y } ) ( ( ( P `
 0 )  =  x  /\  ( P `
 1 )  =  z  /\  ( P `
 2 )  =  y )  /\  (
( I `  ( F `  0 )
)  =  { x ,  z }  /\  ( I `  ( F `  1 )
)  =  { z ,  y } ) ) ) )
28 rexdifsn 4323 . . . . . 6  |-  ( E. z  e.  ( V 
\  { x }
) E. y  e.  ( V  \  {
x ,  z } ) ( ( ( P `  0 )  =  x  /\  ( P `  1 )  =  z  /\  ( P `  2 )  =  y )  /\  ( ( I `  ( F `  0 ) )  =  { x ,  z }  /\  ( I `  ( F `  1 )
)  =  { z ,  y } ) )  <->  E. z  e.  V  ( z  =/=  x  /\  E. y  e.  ( V  \  { x ,  z } ) ( ( ( P `
 0 )  =  x  /\  ( P `
 1 )  =  z  /\  ( P `
 2 )  =  y )  /\  (
( I `  ( F `  0 )
)  =  { x ,  z }  /\  ( I `  ( F `  1 )
)  =  { z ,  y } ) ) ) )
29 rexdifsn 4323 . . . . . 6  |-  ( E. y  e.  ( V 
\  { x }
) E. z  e.  ( V  \  {
x ,  y } ) ( ( ( P `  0 )  =  x  /\  ( P `  1 )  =  z  /\  ( P `  2 )  =  y )  /\  ( ( I `  ( F `  0 ) )  =  { x ,  z }  /\  ( I `  ( F `  1 )
)  =  { z ,  y } ) )  <->  E. y  e.  V  ( y  =/=  x  /\  E. z  e.  ( V  \  { x ,  y } ) ( ( ( P `
 0 )  =  x  /\  ( P `
 1 )  =  z  /\  ( P `
 2 )  =  y )  /\  (
( I `  ( F `  0 )
)  =  { x ,  z }  /\  ( I `  ( F `  1 )
)  =  { z ,  y } ) ) ) )
3027, 28, 293bitr4i 292 . . . . 5  |-  ( E. z  e.  ( V 
\  { x }
) E. y  e.  ( V  \  {
x ,  z } ) ( ( ( P `  0 )  =  x  /\  ( P `  1 )  =  z  /\  ( P `  2 )  =  y )  /\  ( ( I `  ( F `  0 ) )  =  { x ,  z }  /\  ( I `  ( F `  1 )
)  =  { z ,  y } ) )  <->  E. y  e.  ( V  \  { x } ) E. z  e.  ( V  \  {
x ,  y } ) ( ( ( P `  0 )  =  x  /\  ( P `  1 )  =  z  /\  ( P `  2 )  =  y )  /\  ( ( I `  ( F `  0 ) )  =  { x ,  z }  /\  ( I `  ( F `  1 )
)  =  { z ,  y } ) ) )
3130a1i 11 . . . 4  |-  ( ( G  e. USGraph  /\  x  e.  V )  ->  ( E. z  e.  ( V  \  { x }
) E. y  e.  ( V  \  {
x ,  z } ) ( ( ( P `  0 )  =  x  /\  ( P `  1 )  =  z  /\  ( P `  2 )  =  y )  /\  ( ( I `  ( F `  0 ) )  =  { x ,  z }  /\  ( I `  ( F `  1 )
)  =  { z ,  y } ) )  <->  E. y  e.  ( V  \  { x } ) E. z  e.  ( V  \  {
x ,  y } ) ( ( ( P `  0 )  =  x  /\  ( P `  1 )  =  z  /\  ( P `  2 )  =  y )  /\  ( ( I `  ( F `  0 ) )  =  { x ,  z }  /\  ( I `  ( F `  1 )
)  =  { z ,  y } ) ) ) )
3231rexbidva 3049 . . 3  |-  ( G  e. USGraph  ->  ( E. x  e.  V  E. z  e.  ( V  \  {
x } ) E. y  e.  ( V 
\  { x ,  z } ) ( ( ( P ` 
0 )  =  x  /\  ( P ` 
1 )  =  z  /\  ( P ` 
2 )  =  y )  /\  ( ( I `  ( F `
 0 ) )  =  { x ,  z }  /\  (
I `  ( F `  1 ) )  =  { z ,  y } ) )  <->  E. x  e.  V  E. y  e.  ( V  \  { x }
) E. z  e.  ( V  \  {
x ,  y } ) ( ( ( P `  0 )  =  x  /\  ( P `  1 )  =  z  /\  ( P `  2 )  =  y )  /\  ( ( I `  ( F `  0 ) )  =  { x ,  z }  /\  ( I `  ( F `  1 )
)  =  { z ,  y } ) ) ) )
33323anbi3d 1405 . 2  |-  ( G  e. USGraph  ->  ( ( F : ( 0..^ 2 ) -1-1-> dom  I  /\  P : ( 0 ... 2 ) -1-1-> V  /\  E. x  e.  V  E. z  e.  ( V  \  { x } ) E. y  e.  ( V  \  { x ,  z } ) ( ( ( P `
 0 )  =  x  /\  ( P `
 1 )  =  z  /\  ( P `
 2 )  =  y )  /\  (
( I `  ( F `  0 )
)  =  { x ,  z }  /\  ( I `  ( F `  1 )
)  =  { z ,  y } ) ) )  <->  ( F : ( 0..^ 2 ) -1-1-> dom  I  /\  P : ( 0 ... 2 ) -1-1-> V  /\  E. x  e.  V  E. y  e.  ( V  \  { x } ) E. z  e.  ( V  \  { x ,  y } ) ( ( ( P `
 0 )  =  x  /\  ( P `
 1 )  =  z  /\  ( P `
 2 )  =  y )  /\  (
( I `  ( F `  0 )
)  =  { x ,  z }  /\  ( I `  ( F `  1 )
)  =  { z ,  y } ) ) ) ) )
343, 33bitrd 268 1  |-  ( G  e. USGraph  ->  ( ( F (Paths `  G ) P  /\  ( # `  F
)  =  2 )  <-> 
( F : ( 0..^ 2 ) -1-1-> dom  I  /\  P : ( 0 ... 2 )
-1-1-> V  /\  E. x  e.  V  E. y  e.  ( V  \  {
x } ) E. z  e.  ( V 
\  { x ,  y } ) ( ( ( P ` 
0 )  =  x  /\  ( P ` 
1 )  =  z  /\  ( P ` 
2 )  =  y )  /\  ( ( I `  ( F `
 0 ) )  =  { x ,  z }  /\  (
I `  ( F `  1 ) )  =  { z ,  y } ) ) ) ) )
Colors of variables: wff setvar class
Syntax hints:    -> wi 4    <-> wb 196    /\ wa 384    /\ w3a 1037    = wceq 1483    e. wcel 1990    =/= wne 2794   E.wrex 2913    \ cdif 3571   {csn 4177   {cpr 4179   class class class wbr 4653   dom cdm 5114   -1-1->wf1 5885   ` cfv 5888  (class class class)co 6650   0cc0 9936   1c1 9937   2c2 11070   ...cfz 12326  ..^cfzo 12465   #chash 13117  Vtxcvtx 25874  iEdgciedg 25875   USGraph cusgr 26044  Pathscpths 26608
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1722  ax-4 1737  ax-5 1839  ax-6 1888  ax-7 1935  ax-8 1992  ax-9 1999  ax-10 2019  ax-11 2034  ax-12 2047  ax-13 2246  ax-ext 2602  ax-rep 4771  ax-sep 4781  ax-nul 4789  ax-pow 4843  ax-pr 4906  ax-un 6949  ax-cnex 9992  ax-resscn 9993  ax-1cn 9994  ax-icn 9995  ax-addcl 9996  ax-addrcl 9997  ax-mulcl 9998  ax-mulrcl 9999  ax-mulcom 10000  ax-addass 10001  ax-mulass 10002  ax-distr 10003  ax-i2m1 10004  ax-1ne0 10005  ax-1rid 10006  ax-rnegex 10007  ax-rrecex 10008  ax-cnre 10009  ax-pre-lttri 10010  ax-pre-lttrn 10011  ax-pre-ltadd 10012  ax-pre-mulgt0 10013
This theorem depends on definitions:  df-bi 197  df-or 385  df-an 386  df-ifp 1013  df-3or 1038  df-3an 1039  df-tru 1486  df-ex 1705  df-nf 1710  df-sb 1881  df-eu 2474  df-mo 2475  df-clab 2609  df-cleq 2615  df-clel 2618  df-nfc 2753  df-ne 2795  df-nel 2898  df-ral 2917  df-rex 2918  df-reu 2919  df-rmo 2920  df-rab 2921  df-v 3202  df-sbc 3436  df-csb 3534  df-dif 3577  df-un 3579  df-in 3581  df-ss 3588  df-pss 3590  df-nul 3916  df-if 4087  df-pw 4160  df-sn 4178  df-pr 4180  df-tp 4182  df-op 4184  df-uni 4437  df-int 4476  df-iun 4522  df-br 4654  df-opab 4713  df-mpt 4730  df-tr 4753  df-id 5024  df-eprel 5029  df-po 5035  df-so 5036  df-fr 5073  df-we 5075  df-xp 5120  df-rel 5121  df-cnv 5122  df-co 5123  df-dm 5124  df-rn 5125  df-res 5126  df-ima 5127  df-pred 5680  df-ord 5726  df-on 5727  df-lim 5728  df-suc 5729  df-iota 5851  df-fun 5890  df-fn 5891  df-f 5892  df-f1 5893  df-fo 5894  df-f1o 5895  df-fv 5896  df-riota 6611  df-ov 6653  df-oprab 6654  df-mpt2 6655  df-om 7066  df-1st 7168  df-2nd 7169  df-wrecs 7407  df-recs 7468  df-rdg 7506  df-1o 7560  df-2o 7561  df-oadd 7564  df-er 7742  df-map 7859  df-pm 7860  df-en 7956  df-dom 7957  df-sdom 7958  df-fin 7959  df-card 8765  df-cda 8990  df-pnf 10076  df-mnf 10077  df-xr 10078  df-ltxr 10079  df-le 10080  df-sub 10268  df-neg 10269  df-nn 11021  df-2 11079  df-3 11080  df-n0 11293  df-xnn0 11364  df-z 11378  df-uz 11688  df-fz 12327  df-fzo 12466  df-hash 13118  df-word 13299  df-concat 13301  df-s1 13302  df-s2 13593  df-s3 13594  df-edg 25940  df-uhgr 25953  df-upgr 25977  df-umgr 25978  df-uspgr 26045  df-usgr 26046  df-wlks 26495  df-wlkson 26496  df-trls 26589  df-trlson 26590  df-pths 26612  df-spths 26613  df-pthson 26614  df-spthson 26615
This theorem is referenced by: (None)
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