Metamath Proof Explorer


Theorem eupth2lem3lem7

Description: Lemma for eupth2lem3 : Combining trlsegvdeg , eupth2lem3lem3 , eupth2lem3lem4 and eupth2lem3lem6 . (Contributed by Mario Carneiro, 8-Apr-2015) (Revised by AV, 27-Feb-2021)

Ref Expression
Hypotheses trlsegvdeg.v V = Vtx G
trlsegvdeg.i I = iEdg G
trlsegvdeg.f φ Fun I
trlsegvdeg.n φ N 0 ..^ F
trlsegvdeg.u φ U V
trlsegvdeg.w φ F Trails G P
trlsegvdeg.vx φ Vtx X = V
trlsegvdeg.vy φ Vtx Y = V
trlsegvdeg.vz φ Vtx Z = V
trlsegvdeg.ix φ iEdg X = I F 0 ..^ N
trlsegvdeg.iy φ iEdg Y = F N I F N
trlsegvdeg.iz φ iEdg Z = I F 0 N
eupth2lem3.o φ x V | ¬ 2 VtxDeg X x = if P 0 = P N P 0 P N
eupth2lem3.e φ I F N = P N P N + 1
Assertion eupth2lem3lem7 φ ¬ 2 VtxDeg Z U U if P 0 = P N + 1 P 0 P N + 1

Proof

Step Hyp Ref Expression
1 trlsegvdeg.v V = Vtx G
2 trlsegvdeg.i I = iEdg G
3 trlsegvdeg.f φ Fun I
4 trlsegvdeg.n φ N 0 ..^ F
5 trlsegvdeg.u φ U V
6 trlsegvdeg.w φ F Trails G P
7 trlsegvdeg.vx φ Vtx X = V
8 trlsegvdeg.vy φ Vtx Y = V
9 trlsegvdeg.vz φ Vtx Z = V
10 trlsegvdeg.ix φ iEdg X = I F 0 ..^ N
11 trlsegvdeg.iy φ iEdg Y = F N I F N
12 trlsegvdeg.iz φ iEdg Z = I F 0 N
13 eupth2lem3.o φ x V | ¬ 2 VtxDeg X x = if P 0 = P N P 0 P N
14 eupth2lem3.e φ I F N = P N P N + 1
15 1 2 3 4 5 6 7 8 9 10 11 12 trlsegvdeg φ VtxDeg Z U = VtxDeg X U + VtxDeg Y U
16 15 breq2d φ 2 VtxDeg Z U 2 VtxDeg X U + VtxDeg Y U
17 16 notbid φ ¬ 2 VtxDeg Z U ¬ 2 VtxDeg X U + VtxDeg Y U
18 ifpprsnss I F N = P N P N + 1 if- P N = P N + 1 I F N = P N P N P N + 1 I F N
19 14 18 syl φ if- P N = P N + 1 I F N = P N P N P N + 1 I F N
20 1 2 3 4 5 6 7 8 9 10 11 12 13 19 eupth2lem3lem3 φ P N = P N + 1 ¬ 2 VtxDeg X U + VtxDeg Y U U if P 0 = P N + 1 P 0 P N + 1
21 1 2 3 4 5 6 7 8 9 10 11 12 13 14 eupth2lem3lem5 φ I F N 𝒫 V
22 1 2 3 4 5 6 7 8 9 10 11 12 13 19 21 eupth2lem3lem4 φ P N P N + 1 U = P N U = P N + 1 ¬ 2 VtxDeg X U + VtxDeg Y U U if P 0 = P N + 1 P 0 P N + 1
23 22 3expa φ P N P N + 1 U = P N U = P N + 1 ¬ 2 VtxDeg X U + VtxDeg Y U U if P 0 = P N + 1 P 0 P N + 1
24 23 expcom U = P N U = P N + 1 φ P N P N + 1 ¬ 2 VtxDeg X U + VtxDeg Y U U if P 0 = P N + 1 P 0 P N + 1
25 neanior U P N U P N + 1 ¬ U = P N U = P N + 1
26 1 2 3 4 5 6 7 8 9 10 11 12 13 14 eupth2lem3lem6 φ P N P N + 1 U P N U P N + 1 ¬ 2 VtxDeg X U + VtxDeg Y U U if P 0 = P N + 1 P 0 P N + 1
27 26 3expa φ P N P N + 1 U P N U P N + 1 ¬ 2 VtxDeg X U + VtxDeg Y U U if P 0 = P N + 1 P 0 P N + 1
28 27 expcom U P N U P N + 1 φ P N P N + 1 ¬ 2 VtxDeg X U + VtxDeg Y U U if P 0 = P N + 1 P 0 P N + 1
29 25 28 sylbir ¬ U = P N U = P N + 1 φ P N P N + 1 ¬ 2 VtxDeg X U + VtxDeg Y U U if P 0 = P N + 1 P 0 P N + 1
30 24 29 pm2.61i φ P N P N + 1 ¬ 2 VtxDeg X U + VtxDeg Y U U if P 0 = P N + 1 P 0 P N + 1
31 20 30 pm2.61dane φ ¬ 2 VtxDeg X U + VtxDeg Y U U if P 0 = P N + 1 P 0 P N + 1
32 17 31 bitrd φ ¬ 2 VtxDeg Z U U if P 0 = P N + 1 P 0 P N + 1