Metamath Proof Explorer


Theorem 2wlkdlem4

Description: Lemma 4 for 2wlkd . (Contributed by AV, 14-Feb-2021)

Ref Expression
Hypotheses 2wlkd.p P=⟨“ABC”⟩
2wlkd.f F=⟨“JK”⟩
2wlkd.s φAVBVCV
Assertion 2wlkdlem4 φk0FPkV

Proof

Step Hyp Ref Expression
1 2wlkd.p P=⟨“ABC”⟩
2 2wlkd.f F=⟨“JK”⟩
3 2wlkd.s φAVBVCV
4 1 2 3 2wlkdlem3 φP0=AP1=BP2=C
5 simp1 P0=AP1=BP2=CP0=A
6 5 eleq1d P0=AP1=BP2=CP0VAV
7 simp2 P0=AP1=BP2=CP1=B
8 7 eleq1d P0=AP1=BP2=CP1VBV
9 simp3 P0=AP1=BP2=CP2=C
10 9 eleq1d P0=AP1=BP2=CP2VCV
11 6 8 10 3anbi123d P0=AP1=BP2=CP0VP1VP2VAVBVCV
12 11 bicomd P0=AP1=BP2=CAVBVCVP0VP1VP2V
13 4 12 syl φAVBVCVP0VP1VP2V
14 3 13 mpbid φP0VP1VP2V
15 2 fveq2i F=⟨“JK”⟩
16 s2len ⟨“JK”⟩=2
17 15 16 eqtri F=2
18 17 oveq2i 0F=02
19 fz0tp 02=012
20 18 19 eqtri 0F=012
21 20 raleqi k0FPkVk012PkV
22 c0ex 0V
23 1ex 1V
24 2ex 2V
25 fveq2 k=0Pk=P0
26 25 eleq1d k=0PkVP0V
27 fveq2 k=1Pk=P1
28 27 eleq1d k=1PkVP1V
29 fveq2 k=2Pk=P2
30 29 eleq1d k=2PkVP2V
31 22 23 24 26 28 30 raltp k012PkVP0VP1VP2V
32 21 31 bitri k0FPkVP0VP1VP2V
33 14 32 sylibr φk0FPkV