| Step |
Hyp |
Ref |
Expression |
| 1 |
|
clwlkwlk |
|- ( c e. ( ClWalks ` G ) -> c e. ( Walks ` G ) ) |
| 2 |
|
wlkcpr |
|- ( c e. ( Walks ` G ) <-> ( 1st ` c ) ( Walks ` G ) ( 2nd ` c ) ) |
| 3 |
1 2
|
sylib |
|- ( c e. ( ClWalks ` G ) -> ( 1st ` c ) ( Walks ` G ) ( 2nd ` c ) ) |
| 4 |
|
eqid |
|- ( Vtx ` G ) = ( Vtx ` G ) |
| 5 |
4
|
wlkpwrd |
|- ( ( 1st ` c ) ( Walks ` G ) ( 2nd ` c ) -> ( 2nd ` c ) e. Word ( Vtx ` G ) ) |
| 6 |
3 5
|
syl |
|- ( c e. ( ClWalks ` G ) -> ( 2nd ` c ) e. Word ( Vtx ` G ) ) |
| 7 |
6
|
3ad2ant2 |
|- ( ( ( # ` ( 1st ` c ) ) = N /\ c e. ( ClWalks ` G ) /\ N e. ( ZZ>= ` 2 ) ) -> ( 2nd ` c ) e. Word ( Vtx ` G ) ) |
| 8 |
|
eluzge2nn0 |
|- ( N e. ( ZZ>= ` 2 ) -> N e. NN0 ) |
| 9 |
8
|
3ad2ant3 |
|- ( ( ( # ` ( 1st ` c ) ) = N /\ c e. ( ClWalks ` G ) /\ N e. ( ZZ>= ` 2 ) ) -> N e. NN0 ) |
| 10 |
|
eleq1 |
|- ( ( # ` ( 1st ` c ) ) = N -> ( ( # ` ( 1st ` c ) ) e. NN0 <-> N e. NN0 ) ) |
| 11 |
10
|
3ad2ant1 |
|- ( ( ( # ` ( 1st ` c ) ) = N /\ c e. ( ClWalks ` G ) /\ N e. ( ZZ>= ` 2 ) ) -> ( ( # ` ( 1st ` c ) ) e. NN0 <-> N e. NN0 ) ) |
| 12 |
9 11
|
mpbird |
|- ( ( ( # ` ( 1st ` c ) ) = N /\ c e. ( ClWalks ` G ) /\ N e. ( ZZ>= ` 2 ) ) -> ( # ` ( 1st ` c ) ) e. NN0 ) |
| 13 |
|
nn0fz0 |
|- ( ( # ` ( 1st ` c ) ) e. NN0 <-> ( # ` ( 1st ` c ) ) e. ( 0 ... ( # ` ( 1st ` c ) ) ) ) |
| 14 |
12 13
|
sylib |
|- ( ( ( # ` ( 1st ` c ) ) = N /\ c e. ( ClWalks ` G ) /\ N e. ( ZZ>= ` 2 ) ) -> ( # ` ( 1st ` c ) ) e. ( 0 ... ( # ` ( 1st ` c ) ) ) ) |
| 15 |
|
fzelp1 |
|- ( ( # ` ( 1st ` c ) ) e. ( 0 ... ( # ` ( 1st ` c ) ) ) -> ( # ` ( 1st ` c ) ) e. ( 0 ... ( ( # ` ( 1st ` c ) ) + 1 ) ) ) |
| 16 |
14 15
|
syl |
|- ( ( ( # ` ( 1st ` c ) ) = N /\ c e. ( ClWalks ` G ) /\ N e. ( ZZ>= ` 2 ) ) -> ( # ` ( 1st ` c ) ) e. ( 0 ... ( ( # ` ( 1st ` c ) ) + 1 ) ) ) |
| 17 |
|
wlklenvp1 |
|- ( ( 1st ` c ) ( Walks ` G ) ( 2nd ` c ) -> ( # ` ( 2nd ` c ) ) = ( ( # ` ( 1st ` c ) ) + 1 ) ) |
| 18 |
17
|
eqcomd |
|- ( ( 1st ` c ) ( Walks ` G ) ( 2nd ` c ) -> ( ( # ` ( 1st ` c ) ) + 1 ) = ( # ` ( 2nd ` c ) ) ) |
| 19 |
3 18
|
syl |
|- ( c e. ( ClWalks ` G ) -> ( ( # ` ( 1st ` c ) ) + 1 ) = ( # ` ( 2nd ` c ) ) ) |
| 20 |
19
|
oveq2d |
|- ( c e. ( ClWalks ` G ) -> ( 0 ... ( ( # ` ( 1st ` c ) ) + 1 ) ) = ( 0 ... ( # ` ( 2nd ` c ) ) ) ) |
| 21 |
20
|
eleq2d |
|- ( c e. ( ClWalks ` G ) -> ( ( # ` ( 1st ` c ) ) e. ( 0 ... ( ( # ` ( 1st ` c ) ) + 1 ) ) <-> ( # ` ( 1st ` c ) ) e. ( 0 ... ( # ` ( 2nd ` c ) ) ) ) ) |
| 22 |
21
|
3ad2ant2 |
|- ( ( ( # ` ( 1st ` c ) ) = N /\ c e. ( ClWalks ` G ) /\ N e. ( ZZ>= ` 2 ) ) -> ( ( # ` ( 1st ` c ) ) e. ( 0 ... ( ( # ` ( 1st ` c ) ) + 1 ) ) <-> ( # ` ( 1st ` c ) ) e. ( 0 ... ( # ` ( 2nd ` c ) ) ) ) ) |
| 23 |
16 22
|
mpbid |
|- ( ( ( # ` ( 1st ` c ) ) = N /\ c e. ( ClWalks ` G ) /\ N e. ( ZZ>= ` 2 ) ) -> ( # ` ( 1st ` c ) ) e. ( 0 ... ( # ` ( 2nd ` c ) ) ) ) |
| 24 |
|
2nn |
|- 2 e. NN |
| 25 |
24
|
a1i |
|- ( N e. ( ZZ>= ` 2 ) -> 2 e. NN ) |
| 26 |
|
eluz2nn |
|- ( N e. ( ZZ>= ` 2 ) -> N e. NN ) |
| 27 |
|
eluzle |
|- ( N e. ( ZZ>= ` 2 ) -> 2 <_ N ) |
| 28 |
|
elfz1b |
|- ( 2 e. ( 1 ... N ) <-> ( 2 e. NN /\ N e. NN /\ 2 <_ N ) ) |
| 29 |
25 26 27 28
|
syl3anbrc |
|- ( N e. ( ZZ>= ` 2 ) -> 2 e. ( 1 ... N ) ) |
| 30 |
|
ubmelfzo |
|- ( 2 e. ( 1 ... N ) -> ( N - 2 ) e. ( 0 ..^ N ) ) |
| 31 |
29 30
|
syl |
|- ( N e. ( ZZ>= ` 2 ) -> ( N - 2 ) e. ( 0 ..^ N ) ) |
| 32 |
31
|
3ad2ant3 |
|- ( ( ( # ` ( 1st ` c ) ) = N /\ c e. ( ClWalks ` G ) /\ N e. ( ZZ>= ` 2 ) ) -> ( N - 2 ) e. ( 0 ..^ N ) ) |
| 33 |
|
oveq2 |
|- ( ( # ` ( 1st ` c ) ) = N -> ( 0 ..^ ( # ` ( 1st ` c ) ) ) = ( 0 ..^ N ) ) |
| 34 |
33
|
eleq2d |
|- ( ( # ` ( 1st ` c ) ) = N -> ( ( N - 2 ) e. ( 0 ..^ ( # ` ( 1st ` c ) ) ) <-> ( N - 2 ) e. ( 0 ..^ N ) ) ) |
| 35 |
34
|
3ad2ant1 |
|- ( ( ( # ` ( 1st ` c ) ) = N /\ c e. ( ClWalks ` G ) /\ N e. ( ZZ>= ` 2 ) ) -> ( ( N - 2 ) e. ( 0 ..^ ( # ` ( 1st ` c ) ) ) <-> ( N - 2 ) e. ( 0 ..^ N ) ) ) |
| 36 |
32 35
|
mpbird |
|- ( ( ( # ` ( 1st ` c ) ) = N /\ c e. ( ClWalks ` G ) /\ N e. ( ZZ>= ` 2 ) ) -> ( N - 2 ) e. ( 0 ..^ ( # ` ( 1st ` c ) ) ) ) |
| 37 |
|
pfxfv |
|- ( ( ( 2nd ` c ) e. Word ( Vtx ` G ) /\ ( # ` ( 1st ` c ) ) e. ( 0 ... ( # ` ( 2nd ` c ) ) ) /\ ( N - 2 ) e. ( 0 ..^ ( # ` ( 1st ` c ) ) ) ) -> ( ( ( 2nd ` c ) prefix ( # ` ( 1st ` c ) ) ) ` ( N - 2 ) ) = ( ( 2nd ` c ) ` ( N - 2 ) ) ) |
| 38 |
7 23 36 37
|
syl3anc |
|- ( ( ( # ` ( 1st ` c ) ) = N /\ c e. ( ClWalks ` G ) /\ N e. ( ZZ>= ` 2 ) ) -> ( ( ( 2nd ` c ) prefix ( # ` ( 1st ` c ) ) ) ` ( N - 2 ) ) = ( ( 2nd ` c ) ` ( N - 2 ) ) ) |