Metamath Proof Explorer


Theorem 2wlkdlem5

Description: Lemma 5 for 2wlkd . (Contributed by AV, 14-Feb-2021)

Ref Expression
Hypotheses 2wlkd.p P = ⟨“ ABC ”⟩
2wlkd.f F = ⟨“ JK ”⟩
2wlkd.s φ A V B V C V
2wlkd.n φ A B B C
Assertion 2wlkdlem5 φ k 0 ..^ F P k P k + 1

Proof

Step Hyp Ref Expression
1 2wlkd.p P = ⟨“ ABC ”⟩
2 2wlkd.f F = ⟨“ JK ”⟩
3 2wlkd.s φ A V B V C V
4 2wlkd.n φ A B B C
5 1 2 3 2wlkdlem3 φ P 0 = A P 1 = B P 2 = C
6 simp1 P 0 = A P 1 = B P 2 = C P 0 = A
7 simp2 P 0 = A P 1 = B P 2 = C P 1 = B
8 6 7 neeq12d P 0 = A P 1 = B P 2 = C P 0 P 1 A B
9 simp3 P 0 = A P 1 = B P 2 = C P 2 = C
10 7 9 neeq12d P 0 = A P 1 = B P 2 = C P 1 P 2 B C
11 8 10 anbi12d P 0 = A P 1 = B P 2 = C P 0 P 1 P 1 P 2 A B B C
12 11 bicomd P 0 = A P 1 = B P 2 = C A B B C P 0 P 1 P 1 P 2
13 5 12 syl φ A B B C P 0 P 1 P 1 P 2
14 4 13 mpbid φ P 0 P 1 P 1 P 2
15 1 2 2wlkdlem2 0 ..^ F = 0 1
16 15 raleqi k 0 ..^ F P k P k + 1 k 0 1 P k P k + 1
17 c0ex 0 V
18 1ex 1 V
19 fveq2 k = 0 P k = P 0
20 fv0p1e1 k = 0 P k + 1 = P 1
21 19 20 neeq12d k = 0 P k P k + 1 P 0 P 1
22 fveq2 k = 1 P k = P 1
23 oveq1 k = 1 k + 1 = 1 + 1
24 1p1e2 1 + 1 = 2
25 23 24 eqtrdi k = 1 k + 1 = 2
26 25 fveq2d k = 1 P k + 1 = P 2
27 22 26 neeq12d k = 1 P k P k + 1 P 1 P 2
28 17 18 21 27 ralpr k 0 1 P k P k + 1 P 0 P 1 P 1 P 2
29 16 28 bitri k 0 ..^ F P k P k + 1 P 0 P 1 P 1 P 2
30 14 29 sylibr φ k 0 ..^ F P k P k + 1