Metamath Proof Explorer


Theorem wlkp1lem4

Description: Lemma for wlkp1 . (Contributed by AV, 6-Mar-2021)

Ref Expression
Hypotheses wlkp1.v V = Vtx G
wlkp1.i I = iEdg G
wlkp1.f φ Fun I
wlkp1.a φ I Fin
wlkp1.b φ B W
wlkp1.c φ C V
wlkp1.d φ ¬ B dom I
wlkp1.w φ F Walks G P
wlkp1.n N = F
wlkp1.e φ E Edg G
wlkp1.x φ P N C E
wlkp1.u φ iEdg S = I B E
wlkp1.h H = F N B
wlkp1.q Q = P N + 1 C
wlkp1.s φ Vtx S = V
Assertion wlkp1lem4 φ S V H V Q V

Proof

Step Hyp Ref Expression
1 wlkp1.v V = Vtx G
2 wlkp1.i I = iEdg G
3 wlkp1.f φ Fun I
4 wlkp1.a φ I Fin
5 wlkp1.b φ B W
6 wlkp1.c φ C V
7 wlkp1.d φ ¬ B dom I
8 wlkp1.w φ F Walks G P
9 wlkp1.n N = F
10 wlkp1.e φ E Edg G
11 wlkp1.x φ P N C E
12 wlkp1.u φ iEdg S = I B E
13 wlkp1.h H = F N B
14 wlkp1.q Q = P N + 1 C
15 wlkp1.s φ Vtx S = V
16 eqid iEdg G = iEdg G
17 16 wlkf F Walks G P F Word dom iEdg G
18 eqid Vtx G = Vtx G
19 18 wlkp F Walks G P P : 0 F Vtx G
20 17 19 jca F Walks G P F Word dom iEdg G P : 0 F Vtx G
21 8 20 syl φ F Word dom iEdg G P : 0 F Vtx G
22 6 15 eleqtrrd φ C Vtx S
23 22 elfvexd φ S V
24 23 adantr φ F Word dom iEdg G P : 0 F Vtx G S V
25 simprl φ F Word dom iEdg G P : 0 F Vtx G F Word dom iEdg G
26 snex N B V
27 unexg F Word dom iEdg G N B V F N B V
28 25 26 27 sylancl φ F Word dom iEdg G P : 0 F Vtx G F N B V
29 13 28 eqeltrid φ F Word dom iEdg G P : 0 F Vtx G H V
30 ovex 0 F V
31 fvex Vtx G V
32 30 31 fpm P : 0 F Vtx G P Vtx G 𝑝𝑚 0 F
33 32 ad2antll φ F Word dom iEdg G P : 0 F Vtx G P Vtx G 𝑝𝑚 0 F
34 snex N + 1 C V
35 unexg P Vtx G 𝑝𝑚 0 F N + 1 C V P N + 1 C V
36 33 34 35 sylancl φ F Word dom iEdg G P : 0 F Vtx G P N + 1 C V
37 14 36 eqeltrid φ F Word dom iEdg G P : 0 F Vtx G Q V
38 24 29 37 3jca φ F Word dom iEdg G P : 0 F Vtx G S V H V Q V
39 21 38 mpdan φ S V H V Q V