Metamath Proof Explorer


Theorem 3wlkdlem4

Description: Lemma 4 for 3wlkd . (Contributed by Alexander van der Vekens, 11-Nov-2017) (Revised by AV, 7-Feb-2021)

Ref Expression
Hypotheses 3wlkd.p P=⟨“ABCD”⟩
3wlkd.f F=⟨“JKL”⟩
3wlkd.s φAVBVCVDV
Assertion 3wlkdlem4 φk0FPkV

Proof

Step Hyp Ref Expression
1 3wlkd.p P=⟨“ABCD”⟩
2 3wlkd.f F=⟨“JKL”⟩
3 3wlkd.s φAVBVCVDV
4 1 2 3 3wlkdlem3 φP0=AP1=BP2=CP3=D
5 simpl P0=AP1=BP0=A
6 5 eleq1d P0=AP1=BP0VAV
7 simpr P0=AP1=BP1=B
8 7 eleq1d P0=AP1=BP1VBV
9 6 8 anbi12d P0=AP1=BP0VP1VAVBV
10 9 biimparc AVBVP0=AP1=BP0VP1V
11 c0ex 0V
12 1ex 1V
13 11 12 pm3.2i 0V1V
14 fveq2 k=0Pk=P0
15 14 eleq1d k=0PkVP0V
16 fveq2 k=1Pk=P1
17 16 eleq1d k=1PkVP1V
18 15 17 ralprg 0V1Vk01PkVP0VP1V
19 13 18 mp1i AVBVP0=AP1=Bk01PkVP0VP1V
20 10 19 mpbird AVBVP0=AP1=Bk01PkV
21 20 ex AVBVP0=AP1=Bk01PkV
22 simpl P2=CP3=DP2=C
23 22 eleq1d P2=CP3=DP2VCV
24 simpr P2=CP3=DP3=D
25 24 eleq1d P2=CP3=DP3VDV
26 23 25 anbi12d P2=CP3=DP2VP3VCVDV
27 26 biimparc CVDVP2=CP3=DP2VP3V
28 2ex 2V
29 3ex 3V
30 28 29 pm3.2i 2V3V
31 fveq2 k=2Pk=P2
32 31 eleq1d k=2PkVP2V
33 fveq2 k=3Pk=P3
34 33 eleq1d k=3PkVP3V
35 32 34 ralprg 2V3Vk23PkVP2VP3V
36 30 35 mp1i CVDVP2=CP3=Dk23PkVP2VP3V
37 27 36 mpbird CVDVP2=CP3=Dk23PkV
38 37 ex CVDVP2=CP3=Dk23PkV
39 21 38 im2anan9 AVBVCVDVP0=AP1=BP2=CP3=Dk01PkVk23PkV
40 3 4 39 sylc φk01PkVk23PkV
41 2 fveq2i F=⟨“JKL”⟩
42 s3len ⟨“JKL”⟩=3
43 41 42 eqtri F=3
44 43 oveq2i 0F=03
45 fz0to3un2pr 03=0123
46 44 45 eqtri 0F=0123
47 46 raleqi k0FPkVk0123PkV
48 ralunb k0123PkVk01PkVk23PkV
49 47 48 bitri k0FPkVk01PkVk23PkV
50 40 49 sylibr φk0FPkV