Metamath Proof Explorer


Theorem wlk2f

Description: If there is a walk W there is a pair of functions representing this walk. (Contributed by Alexander van der Vekens, 22-Jul-2018)

Ref Expression
Assertion wlk2f ( 𝑊 ∈ ( Walks ‘ 𝐺 ) → ∃ 𝑓𝑝 𝑓 ( Walks ‘ 𝐺 ) 𝑝 )

Proof

Step Hyp Ref Expression
1 wlkcpr ( 𝑊 ∈ ( Walks ‘ 𝐺 ) ↔ ( 1st𝑊 ) ( Walks ‘ 𝐺 ) ( 2nd𝑊 ) )
2 fvex ( 1st𝑊 ) ∈ V
3 fvex ( 2nd𝑊 ) ∈ V
4 breq12 ( ( 𝑓 = ( 1st𝑊 ) ∧ 𝑝 = ( 2nd𝑊 ) ) → ( 𝑓 ( Walks ‘ 𝐺 ) 𝑝 ↔ ( 1st𝑊 ) ( Walks ‘ 𝐺 ) ( 2nd𝑊 ) ) )
5 2 3 4 spc2ev ( ( 1st𝑊 ) ( Walks ‘ 𝐺 ) ( 2nd𝑊 ) → ∃ 𝑓𝑝 𝑓 ( Walks ‘ 𝐺 ) 𝑝 )
6 1 5 sylbi ( 𝑊 ∈ ( Walks ‘ 𝐺 ) → ∃ 𝑓𝑝 𝑓 ( Walks ‘ 𝐺 ) 𝑝 )