Metamath Proof Explorer


Theorem clwlkclwwlkf1lem2

Description: Lemma 2 for clwlkclwwlkf1 . (Contributed by AV, 24-May-2022) (Revised by AV, 30-Oct-2022)

Ref Expression
Hypotheses clwlkclwwlkf.c C = w ClWalks G | 1 1 st w
clwlkclwwlkf.a A = 1 st U
clwlkclwwlkf.b B = 2 nd U
clwlkclwwlkf.d D = 1 st W
clwlkclwwlkf.e E = 2 nd W
Assertion clwlkclwwlkf1lem2 U C W C B prefix A = E prefix D A = D i 0 ..^ A B i = E i

Proof

Step Hyp Ref Expression
1 clwlkclwwlkf.c C = w ClWalks G | 1 1 st w
2 clwlkclwwlkf.a A = 1 st U
3 clwlkclwwlkf.b B = 2 nd U
4 clwlkclwwlkf.d D = 1 st W
5 clwlkclwwlkf.e E = 2 nd W
6 1 2 3 clwlkclwwlkflem U C A Walks G B B 0 = B A A
7 1 4 5 clwlkclwwlkflem W C D Walks G E E 0 = E D D
8 6 7 anim12i U C W C A Walks G B B 0 = B A A D Walks G E E 0 = E D D
9 eqid Vtx G = Vtx G
10 9 wlkpwrd A Walks G B B Word Vtx G
11 10 3ad2ant1 A Walks G B B 0 = B A A B Word Vtx G
12 9 wlkpwrd D Walks G E E Word Vtx G
13 12 3ad2ant1 D Walks G E E 0 = E D D E Word Vtx G
14 11 13 anim12i A Walks G B B 0 = B A A D Walks G E E 0 = E D D B Word Vtx G E Word Vtx G
15 nnnn0 A A 0
16 15 3ad2ant3 A Walks G B B 0 = B A A A 0
17 nnnn0 D D 0
18 17 3ad2ant3 D Walks G E E 0 = E D D D 0
19 16 18 anim12i A Walks G B B 0 = B A A D Walks G E E 0 = E D D A 0 D 0
20 wlklenvp1 A Walks G B B = A + 1
21 nnre A A
22 21 lep1d A A A + 1
23 breq2 B = A + 1 A B A A + 1
24 22 23 syl5ibr B = A + 1 A A B
25 20 24 syl A Walks G B A A B
26 25 a1d A Walks G B B 0 = B A A A B
27 26 3imp A Walks G B B 0 = B A A A B
28 wlklenvp1 D Walks G E E = D + 1
29 nnre D D
30 29 lep1d D D D + 1
31 breq2 E = D + 1 D E D D + 1
32 30 31 syl5ibr E = D + 1 D D E
33 28 32 syl D Walks G E D D E
34 33 a1d D Walks G E E 0 = E D D D E
35 34 3imp D Walks G E E 0 = E D D D E
36 27 35 anim12i A Walks G B B 0 = B A A D Walks G E E 0 = E D D A B D E
37 14 19 36 3jca A Walks G B B 0 = B A A D Walks G E E 0 = E D D B Word Vtx G E Word Vtx G A 0 D 0 A B D E
38 pfxeq B Word Vtx G E Word Vtx G A 0 D 0 A B D E B prefix A = E prefix D A = D i 0 ..^ A B i = E i
39 8 37 38 3syl U C W C B prefix A = E prefix D A = D i 0 ..^ A B i = E i
40 39 biimp3a U C W C B prefix A = E prefix D A = D i 0 ..^ A B i = E i