Metamath Proof Explorer


Theorem pgnioedg5

Description: An inside and an outside vertex not adjacent in a Petersen graph. (Contributed by AV, 21-Nov-2025)

Ref Expression
Hypotheses pgnioedg1.g
|- G = ( 5 gPetersenGr 2 )
pgnioedg1.e
|- E = ( Edg ` G )
Assertion pgnioedg5
|- ( y e. ( 0 ..^ 5 ) -> -. { <. 1 , ( ( y - 1 ) mod 5 ) >. , <. 0 , ( ( y + 1 ) mod 5 ) >. } e. E )

Proof

Step Hyp Ref Expression
1 pgnioedg1.g
 |-  G = ( 5 gPetersenGr 2 )
2 pgnioedg1.e
 |-  E = ( Edg ` G )
3 5eluz3
 |-  5 e. ( ZZ>= ` 3 )
4 pglem
 |-  2 e. ( 1 ..^ ( |^ ` ( 5 / 2 ) ) )
5 3 4 pm3.2i
 |-  ( 5 e. ( ZZ>= ` 3 ) /\ 2 e. ( 1 ..^ ( |^ ` ( 5 / 2 ) ) ) )
6 1ex
 |-  1 e. _V
7 ovex
 |-  ( ( y - 1 ) mod 5 ) e. _V
8 6 7 op1st
 |-  ( 1st ` <. 1 , ( ( y - 1 ) mod 5 ) >. ) = 1
9 simpr
 |-  ( ( y e. ( 0 ..^ 5 ) /\ { <. 1 , ( ( y - 1 ) mod 5 ) >. , <. 0 , ( ( y + 1 ) mod 5 ) >. } e. E ) -> { <. 1 , ( ( y - 1 ) mod 5 ) >. , <. 0 , ( ( y + 1 ) mod 5 ) >. } e. E )
10 eqid
 |-  ( 1 ..^ ( |^ ` ( 5 / 2 ) ) ) = ( 1 ..^ ( |^ ` ( 5 / 2 ) ) )
11 eqid
 |-  ( Vtx ` G ) = ( Vtx ` G )
12 10 1 11 2 gpgvtxedg1
 |-  ( ( ( 5 e. ( ZZ>= ` 3 ) /\ 2 e. ( 1 ..^ ( |^ ` ( 5 / 2 ) ) ) ) /\ ( 1st ` <. 1 , ( ( y - 1 ) mod 5 ) >. ) = 1 /\ { <. 1 , ( ( y - 1 ) mod 5 ) >. , <. 0 , ( ( y + 1 ) mod 5 ) >. } e. E ) -> ( <. 0 , ( ( y + 1 ) mod 5 ) >. = <. 1 , ( ( ( 2nd ` <. 1 , ( ( y - 1 ) mod 5 ) >. ) + 2 ) mod 5 ) >. \/ <. 0 , ( ( y + 1 ) mod 5 ) >. = <. 0 , ( 2nd ` <. 1 , ( ( y - 1 ) mod 5 ) >. ) >. \/ <. 0 , ( ( y + 1 ) mod 5 ) >. = <. 1 , ( ( ( 2nd ` <. 1 , ( ( y - 1 ) mod 5 ) >. ) - 2 ) mod 5 ) >. ) )
13 5 8 9 12 mp3an12i
 |-  ( ( y e. ( 0 ..^ 5 ) /\ { <. 1 , ( ( y - 1 ) mod 5 ) >. , <. 0 , ( ( y + 1 ) mod 5 ) >. } e. E ) -> ( <. 0 , ( ( y + 1 ) mod 5 ) >. = <. 1 , ( ( ( 2nd ` <. 1 , ( ( y - 1 ) mod 5 ) >. ) + 2 ) mod 5 ) >. \/ <. 0 , ( ( y + 1 ) mod 5 ) >. = <. 0 , ( 2nd ` <. 1 , ( ( y - 1 ) mod 5 ) >. ) >. \/ <. 0 , ( ( y + 1 ) mod 5 ) >. = <. 1 , ( ( ( 2nd ` <. 1 , ( ( y - 1 ) mod 5 ) >. ) - 2 ) mod 5 ) >. ) )
14 13 ex
 |-  ( y e. ( 0 ..^ 5 ) -> ( { <. 1 , ( ( y - 1 ) mod 5 ) >. , <. 0 , ( ( y + 1 ) mod 5 ) >. } e. E -> ( <. 0 , ( ( y + 1 ) mod 5 ) >. = <. 1 , ( ( ( 2nd ` <. 1 , ( ( y - 1 ) mod 5 ) >. ) + 2 ) mod 5 ) >. \/ <. 0 , ( ( y + 1 ) mod 5 ) >. = <. 0 , ( 2nd ` <. 1 , ( ( y - 1 ) mod 5 ) >. ) >. \/ <. 0 , ( ( y + 1 ) mod 5 ) >. = <. 1 , ( ( ( 2nd ` <. 1 , ( ( y - 1 ) mod 5 ) >. ) - 2 ) mod 5 ) >. ) ) )
15 c0ex
 |-  0 e. _V
16 ovex
 |-  ( ( y + 1 ) mod 5 ) e. _V
17 15 16 opth
 |-  ( <. 0 , ( ( y + 1 ) mod 5 ) >. = <. 1 , ( ( ( 2nd ` <. 1 , ( ( y - 1 ) mod 5 ) >. ) + 2 ) mod 5 ) >. <-> ( 0 = 1 /\ ( ( y + 1 ) mod 5 ) = ( ( ( 2nd ` <. 1 , ( ( y - 1 ) mod 5 ) >. ) + 2 ) mod 5 ) ) )
18 0ne1
 |-  0 =/= 1
19 eqneqall
 |-  ( 0 = 1 -> ( 0 =/= 1 -> -. { <. 1 , ( ( y - 1 ) mod 5 ) >. , <. 0 , ( ( y + 1 ) mod 5 ) >. } e. E ) )
20 18 19 mpi
 |-  ( 0 = 1 -> -. { <. 1 , ( ( y - 1 ) mod 5 ) >. , <. 0 , ( ( y + 1 ) mod 5 ) >. } e. E )
21 20 adantr
 |-  ( ( 0 = 1 /\ ( ( y + 1 ) mod 5 ) = ( ( ( 2nd ` <. 1 , ( ( y - 1 ) mod 5 ) >. ) + 2 ) mod 5 ) ) -> -. { <. 1 , ( ( y - 1 ) mod 5 ) >. , <. 0 , ( ( y + 1 ) mod 5 ) >. } e. E )
22 17 21 sylbi
 |-  ( <. 0 , ( ( y + 1 ) mod 5 ) >. = <. 1 , ( ( ( 2nd ` <. 1 , ( ( y - 1 ) mod 5 ) >. ) + 2 ) mod 5 ) >. -> -. { <. 1 , ( ( y - 1 ) mod 5 ) >. , <. 0 , ( ( y + 1 ) mod 5 ) >. } e. E )
23 22 a1i
 |-  ( y e. ( 0 ..^ 5 ) -> ( <. 0 , ( ( y + 1 ) mod 5 ) >. = <. 1 , ( ( ( 2nd ` <. 1 , ( ( y - 1 ) mod 5 ) >. ) + 2 ) mod 5 ) >. -> -. { <. 1 , ( ( y - 1 ) mod 5 ) >. , <. 0 , ( ( y + 1 ) mod 5 ) >. } e. E ) )
24 15 16 opth
 |-  ( <. 0 , ( ( y + 1 ) mod 5 ) >. = <. 0 , ( 2nd ` <. 1 , ( ( y - 1 ) mod 5 ) >. ) >. <-> ( 0 = 0 /\ ( ( y + 1 ) mod 5 ) = ( 2nd ` <. 1 , ( ( y - 1 ) mod 5 ) >. ) ) )
25 6 7 op2nd
 |-  ( 2nd ` <. 1 , ( ( y - 1 ) mod 5 ) >. ) = ( ( y - 1 ) mod 5 )
26 25 eqeq2i
 |-  ( ( ( y + 1 ) mod 5 ) = ( 2nd ` <. 1 , ( ( y - 1 ) mod 5 ) >. ) <-> ( ( y + 1 ) mod 5 ) = ( ( y - 1 ) mod 5 ) )
27 eqid
 |-  ( 0 ..^ 5 ) = ( 0 ..^ 5 )
28 27 modm1nep1
 |-  ( ( 5 e. ( ZZ>= ` 3 ) /\ y e. ( 0 ..^ 5 ) ) -> ( ( y - 1 ) mod 5 ) =/= ( ( y + 1 ) mod 5 ) )
29 3 28 mpan
 |-  ( y e. ( 0 ..^ 5 ) -> ( ( y - 1 ) mod 5 ) =/= ( ( y + 1 ) mod 5 ) )
30 29 necomd
 |-  ( y e. ( 0 ..^ 5 ) -> ( ( y + 1 ) mod 5 ) =/= ( ( y - 1 ) mod 5 ) )
31 eqneqall
 |-  ( ( ( y + 1 ) mod 5 ) = ( ( y - 1 ) mod 5 ) -> ( ( ( y + 1 ) mod 5 ) =/= ( ( y - 1 ) mod 5 ) -> -. { <. 1 , ( ( y - 1 ) mod 5 ) >. , <. 0 , ( ( y + 1 ) mod 5 ) >. } e. E ) )
32 30 31 syl5
 |-  ( ( ( y + 1 ) mod 5 ) = ( ( y - 1 ) mod 5 ) -> ( y e. ( 0 ..^ 5 ) -> -. { <. 1 , ( ( y - 1 ) mod 5 ) >. , <. 0 , ( ( y + 1 ) mod 5 ) >. } e. E ) )
33 26 32 sylbi
 |-  ( ( ( y + 1 ) mod 5 ) = ( 2nd ` <. 1 , ( ( y - 1 ) mod 5 ) >. ) -> ( y e. ( 0 ..^ 5 ) -> -. { <. 1 , ( ( y - 1 ) mod 5 ) >. , <. 0 , ( ( y + 1 ) mod 5 ) >. } e. E ) )
34 24 33 simplbiim
 |-  ( <. 0 , ( ( y + 1 ) mod 5 ) >. = <. 0 , ( 2nd ` <. 1 , ( ( y - 1 ) mod 5 ) >. ) >. -> ( y e. ( 0 ..^ 5 ) -> -. { <. 1 , ( ( y - 1 ) mod 5 ) >. , <. 0 , ( ( y + 1 ) mod 5 ) >. } e. E ) )
35 34 com12
 |-  ( y e. ( 0 ..^ 5 ) -> ( <. 0 , ( ( y + 1 ) mod 5 ) >. = <. 0 , ( 2nd ` <. 1 , ( ( y - 1 ) mod 5 ) >. ) >. -> -. { <. 1 , ( ( y - 1 ) mod 5 ) >. , <. 0 , ( ( y + 1 ) mod 5 ) >. } e. E ) )
36 15 16 opth
 |-  ( <. 0 , ( ( y + 1 ) mod 5 ) >. = <. 1 , ( ( ( 2nd ` <. 1 , ( ( y - 1 ) mod 5 ) >. ) - 2 ) mod 5 ) >. <-> ( 0 = 1 /\ ( ( y + 1 ) mod 5 ) = ( ( ( 2nd ` <. 1 , ( ( y - 1 ) mod 5 ) >. ) - 2 ) mod 5 ) ) )
37 20 adantr
 |-  ( ( 0 = 1 /\ ( ( y + 1 ) mod 5 ) = ( ( ( 2nd ` <. 1 , ( ( y - 1 ) mod 5 ) >. ) - 2 ) mod 5 ) ) -> -. { <. 1 , ( ( y - 1 ) mod 5 ) >. , <. 0 , ( ( y + 1 ) mod 5 ) >. } e. E )
38 36 37 sylbi
 |-  ( <. 0 , ( ( y + 1 ) mod 5 ) >. = <. 1 , ( ( ( 2nd ` <. 1 , ( ( y - 1 ) mod 5 ) >. ) - 2 ) mod 5 ) >. -> -. { <. 1 , ( ( y - 1 ) mod 5 ) >. , <. 0 , ( ( y + 1 ) mod 5 ) >. } e. E )
39 38 a1i
 |-  ( y e. ( 0 ..^ 5 ) -> ( <. 0 , ( ( y + 1 ) mod 5 ) >. = <. 1 , ( ( ( 2nd ` <. 1 , ( ( y - 1 ) mod 5 ) >. ) - 2 ) mod 5 ) >. -> -. { <. 1 , ( ( y - 1 ) mod 5 ) >. , <. 0 , ( ( y + 1 ) mod 5 ) >. } e. E ) )
40 23 35 39 3jaod
 |-  ( y e. ( 0 ..^ 5 ) -> ( ( <. 0 , ( ( y + 1 ) mod 5 ) >. = <. 1 , ( ( ( 2nd ` <. 1 , ( ( y - 1 ) mod 5 ) >. ) + 2 ) mod 5 ) >. \/ <. 0 , ( ( y + 1 ) mod 5 ) >. = <. 0 , ( 2nd ` <. 1 , ( ( y - 1 ) mod 5 ) >. ) >. \/ <. 0 , ( ( y + 1 ) mod 5 ) >. = <. 1 , ( ( ( 2nd ` <. 1 , ( ( y - 1 ) mod 5 ) >. ) - 2 ) mod 5 ) >. ) -> -. { <. 1 , ( ( y - 1 ) mod 5 ) >. , <. 0 , ( ( y + 1 ) mod 5 ) >. } e. E ) )
41 14 40 syld
 |-  ( y e. ( 0 ..^ 5 ) -> ( { <. 1 , ( ( y - 1 ) mod 5 ) >. , <. 0 , ( ( y + 1 ) mod 5 ) >. } e. E -> -. { <. 1 , ( ( y - 1 ) mod 5 ) >. , <. 0 , ( ( y + 1 ) mod 5 ) >. } e. E ) )
42 41 pm2.01d
 |-  ( y e. ( 0 ..^ 5 ) -> -. { <. 1 , ( ( y - 1 ) mod 5 ) >. , <. 0 , ( ( y + 1 ) mod 5 ) >. } e. E )