Metamath Proof Explorer


Theorem wlkonprop

Description: Properties of a walk between two vertices. (Contributed by Alexander van der Vekens, 12-Dec-2017) (Revised by AV, 31-Dec-2020) (Proof shortened by AV, 16-Jan-2021)

Ref Expression
Hypothesis wlkson.v ⊢ V = Vtx ⁡ G
Assertion wlkonprop ⊢ F A WalksOn ⁡ G B P → G ∈ V ∧ A ∈ V ∧ B ∈ V ∧ F ∈ V ∧ P ∈ V ∧ F Walks ⁡ G P ∧ P ⁡ 0 = A ∧ P ⁡ F = B

Proof

Step Hyp Ref Expression
1 wlkson.v ⊢ V = Vtx ⁡ G
2 1 fvexi ⊢ V ∈ V
3 df-wlkson ⊢ WalksOn = g ∈ V ⟼ a ∈ Vtx ⁡ g , b ∈ Vtx ⁡ g ⟼ f p | f Walks ⁡ g p ∧ p ⁡ 0 = a ∧ p ⁡ f = b
4 1 wlkson ⊢ A ∈ V ∧ B ∈ V → A WalksOn ⁡ G B = f p | f Walks ⁡ G p ∧ p ⁡ 0 = A ∧ p ⁡ f = B
5 4 3adant1 ⊢ G ∈ V ∧ A ∈ V ∧ B ∈ V → A WalksOn ⁡ G B = f p | f Walks ⁡ G p ∧ p ⁡ 0 = A ∧ p ⁡ f = B
6 fveq2 ⊢ g = G → Vtx ⁡ g = Vtx ⁡ G
7 6 1 eqtr4di ⊢ g = G → Vtx ⁡ g = V
8 fveq2 ⊢ g = G → Walks ⁡ g = Walks ⁡ G
9 8 breqd ⊢ g = G → f Walks ⁡ g p ↔ f Walks ⁡ G p
10 9 3anbi1d ⊢ g = G → f Walks ⁡ g p ∧ p ⁡ 0 = a ∧ p ⁡ f = b ↔ f Walks ⁡ G p ∧ p ⁡ 0 = a ∧ p ⁡ f = b
11 3 5 7 7 10 bropfvvvv ⊢ V ∈ V ∧ V ∈ V → F A WalksOn ⁡ G B P → G ∈ V ∧ A ∈ V ∧ B ∈ V ∧ F ∈ V ∧ P ∈ V
12 2 2 11 mp2an ⊢ F A WalksOn ⁡ G B P → G ∈ V ∧ A ∈ V ∧ B ∈ V ∧ F ∈ V ∧ P ∈ V
13 3anass ⊢ G ∈ V ∧ A ∈ V ∧ B ∈ V ↔ G ∈ V ∧ A ∈ V ∧ B ∈ V
14 13 anbi1i ⊢ G ∈ V ∧ A ∈ V ∧ B ∈ V ∧ F ∈ V ∧ P ∈ V ↔ G ∈ V ∧ A ∈ V ∧ B ∈ V ∧ F ∈ V ∧ P ∈ V
15 df-3an ⊢ G ∈ V ∧ A ∈ V ∧ B ∈ V ∧ F ∈ V ∧ P ∈ V ↔ G ∈ V ∧ A ∈ V ∧ B ∈ V ∧ F ∈ V ∧ P ∈ V
16 14 15 bitr4i ⊢ G ∈ V ∧ A ∈ V ∧ B ∈ V ∧ F ∈ V ∧ P ∈ V ↔ G ∈ V ∧ A ∈ V ∧ B ∈ V ∧ F ∈ V ∧ P ∈ V
17 12 16 sylibr ⊢ F A WalksOn ⁡ G B P → G ∈ V ∧ A ∈ V ∧ B ∈ V ∧ F ∈ V ∧ P ∈ V
18 1 iswlkon ⊢ A ∈ V ∧ B ∈ V ∧ F ∈ V ∧ P ∈ V → F A WalksOn ⁡ G B P ↔ F Walks ⁡ G P ∧ P ⁡ 0 = A ∧ P ⁡ F = B
19 18 3adantl1 ⊢ G ∈ V ∧ A ∈ V ∧ B ∈ V ∧ F ∈ V ∧ P ∈ V → F A WalksOn ⁡ G B P ↔ F Walks ⁡ G P ∧ P ⁡ 0 = A ∧ P ⁡ F = B
20 19 biimpd ⊢ G ∈ V ∧ A ∈ V ∧ B ∈ V ∧ F ∈ V ∧ P ∈ V → F A WalksOn ⁡ G B P → F Walks ⁡ G P ∧ P ⁡ 0 = A ∧ P ⁡ F = B
21 20 imdistani ⊢ G ∈ V ∧ A ∈ V ∧ B ∈ V ∧ F ∈ V ∧ P ∈ V ∧ F A WalksOn ⁡ G B P → G ∈ V ∧ A ∈ V ∧ B ∈ V ∧ F ∈ V ∧ P ∈ V ∧ F Walks ⁡ G P ∧ P ⁡ 0 = A ∧ P ⁡ F = B
22 17 21 mpancom ⊢ F A WalksOn ⁡ G B P → G ∈ V ∧ A ∈ V ∧ B ∈ V ∧ F ∈ V ∧ P ∈ V ∧ F Walks ⁡ G P ∧ P ⁡ 0 = A ∧ P ⁡ F = B
23 df-3an ⊢ G ∈ V ∧ A ∈ V ∧ B ∈ V ∧ F ∈ V ∧ P ∈ V ∧ F Walks ⁡ G P ∧ P ⁡ 0 = A ∧ P ⁡ F = B ↔ G ∈ V ∧ A ∈ V ∧ B ∈ V ∧ F ∈ V ∧ P ∈ V ∧ F Walks ⁡ G P ∧ P ⁡ 0 = A ∧ P ⁡ F = B
24 22 23 sylibr ⊢ F A WalksOn ⁡ G B P → G ∈ V ∧ A ∈ V ∧ B ∈ V ∧ F ∈ V ∧ P ∈ V ∧ F Walks ⁡ G P ∧ P ⁡ 0 = A ∧ P ⁡ F = B