Metamath Proof Explorer


Theorem subgrwlk

Description: If a walk exists in a subgraph of a graph G , then that walk also exists in G . (Contributed by BTernaryTau, 22-Oct-2023)

Ref Expression
Assertion subgrwlk ( 𝑆 SubGraph 𝐺 → ( 𝐹 ( Walks ‘ 𝑆 ) 𝑃𝐹 ( Walks ‘ 𝐺 ) 𝑃 ) )

Proof

Step Hyp Ref Expression
1 subgrv ( 𝑆 SubGraph 𝐺 → ( 𝑆 ∈ V ∧ 𝐺 ∈ V ) )
2 1 simpld ( 𝑆 SubGraph 𝐺𝑆 ∈ V )
3 eqid ( Vtx ‘ 𝑆 ) = ( Vtx ‘ 𝑆 )
4 eqid ( iEdg ‘ 𝑆 ) = ( iEdg ‘ 𝑆 )
5 3 4 iswlkg ( 𝑆 ∈ V → ( 𝐹 ( Walks ‘ 𝑆 ) 𝑃 ↔ ( 𝐹 ∈ Word dom ( iEdg ‘ 𝑆 ) ∧ 𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ ( Vtx ‘ 𝑆 ) ∧ ∀ 𝑘 ∈ ( 0 ..^ ( ♯ ‘ 𝐹 ) ) if- ( ( 𝑃𝑘 ) = ( 𝑃 ‘ ( 𝑘 + 1 ) ) , ( ( iEdg ‘ 𝑆 ) ‘ ( 𝐹𝑘 ) ) = { ( 𝑃𝑘 ) } , { ( 𝑃𝑘 ) , ( 𝑃 ‘ ( 𝑘 + 1 ) ) } ⊆ ( ( iEdg ‘ 𝑆 ) ‘ ( 𝐹𝑘 ) ) ) ) ) )
6 2 5 syl ( 𝑆 SubGraph 𝐺 → ( 𝐹 ( Walks ‘ 𝑆 ) 𝑃 ↔ ( 𝐹 ∈ Word dom ( iEdg ‘ 𝑆 ) ∧ 𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ ( Vtx ‘ 𝑆 ) ∧ ∀ 𝑘 ∈ ( 0 ..^ ( ♯ ‘ 𝐹 ) ) if- ( ( 𝑃𝑘 ) = ( 𝑃 ‘ ( 𝑘 + 1 ) ) , ( ( iEdg ‘ 𝑆 ) ‘ ( 𝐹𝑘 ) ) = { ( 𝑃𝑘 ) } , { ( 𝑃𝑘 ) , ( 𝑃 ‘ ( 𝑘 + 1 ) ) } ⊆ ( ( iEdg ‘ 𝑆 ) ‘ ( 𝐹𝑘 ) ) ) ) ) )
7 3simpa ( ( 𝐹 ∈ Word dom ( iEdg ‘ 𝑆 ) ∧ 𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ ( Vtx ‘ 𝑆 ) ∧ ∀ 𝑘 ∈ ( 0 ..^ ( ♯ ‘ 𝐹 ) ) if- ( ( 𝑃𝑘 ) = ( 𝑃 ‘ ( 𝑘 + 1 ) ) , ( ( iEdg ‘ 𝑆 ) ‘ ( 𝐹𝑘 ) ) = { ( 𝑃𝑘 ) } , { ( 𝑃𝑘 ) , ( 𝑃 ‘ ( 𝑘 + 1 ) ) } ⊆ ( ( iEdg ‘ 𝑆 ) ‘ ( 𝐹𝑘 ) ) ) ) → ( 𝐹 ∈ Word dom ( iEdg ‘ 𝑆 ) ∧ 𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ ( Vtx ‘ 𝑆 ) ) )
8 eqid ( Vtx ‘ 𝐺 ) = ( Vtx ‘ 𝐺 )
9 eqid ( iEdg ‘ 𝐺 ) = ( iEdg ‘ 𝐺 )
10 eqid ( Edg ‘ 𝑆 ) = ( Edg ‘ 𝑆 )
11 3 8 4 9 10 subgrprop2 ( 𝑆 SubGraph 𝐺 → ( ( Vtx ‘ 𝑆 ) ⊆ ( Vtx ‘ 𝐺 ) ∧ ( iEdg ‘ 𝑆 ) ⊆ ( iEdg ‘ 𝐺 ) ∧ ( Edg ‘ 𝑆 ) ⊆ 𝒫 ( Vtx ‘ 𝑆 ) ) )
12 11 simp2d ( 𝑆 SubGraph 𝐺 → ( iEdg ‘ 𝑆 ) ⊆ ( iEdg ‘ 𝐺 ) )
13 dmss ( ( iEdg ‘ 𝑆 ) ⊆ ( iEdg ‘ 𝐺 ) → dom ( iEdg ‘ 𝑆 ) ⊆ dom ( iEdg ‘ 𝐺 ) )
14 sswrd ( dom ( iEdg ‘ 𝑆 ) ⊆ dom ( iEdg ‘ 𝐺 ) → Word dom ( iEdg ‘ 𝑆 ) ⊆ Word dom ( iEdg ‘ 𝐺 ) )
15 12 13 14 3syl ( 𝑆 SubGraph 𝐺 → Word dom ( iEdg ‘ 𝑆 ) ⊆ Word dom ( iEdg ‘ 𝐺 ) )
16 15 sseld ( 𝑆 SubGraph 𝐺 → ( 𝐹 ∈ Word dom ( iEdg ‘ 𝑆 ) → 𝐹 ∈ Word dom ( iEdg ‘ 𝐺 ) ) )
17 11 simp1d ( 𝑆 SubGraph 𝐺 → ( Vtx ‘ 𝑆 ) ⊆ ( Vtx ‘ 𝐺 ) )
18 fss ( ( 𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ ( Vtx ‘ 𝑆 ) ∧ ( Vtx ‘ 𝑆 ) ⊆ ( Vtx ‘ 𝐺 ) ) → 𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ ( Vtx ‘ 𝐺 ) )
19 18 expcom ( ( Vtx ‘ 𝑆 ) ⊆ ( Vtx ‘ 𝐺 ) → ( 𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ ( Vtx ‘ 𝑆 ) → 𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ ( Vtx ‘ 𝐺 ) ) )
20 17 19 syl ( 𝑆 SubGraph 𝐺 → ( 𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ ( Vtx ‘ 𝑆 ) → 𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ ( Vtx ‘ 𝐺 ) ) )
21 16 20 anim12d ( 𝑆 SubGraph 𝐺 → ( ( 𝐹 ∈ Word dom ( iEdg ‘ 𝑆 ) ∧ 𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ ( Vtx ‘ 𝑆 ) ) → ( 𝐹 ∈ Word dom ( iEdg ‘ 𝐺 ) ∧ 𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ ( Vtx ‘ 𝐺 ) ) ) )
22 7 21 syl5 ( 𝑆 SubGraph 𝐺 → ( ( 𝐹 ∈ Word dom ( iEdg ‘ 𝑆 ) ∧ 𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ ( Vtx ‘ 𝑆 ) ∧ ∀ 𝑘 ∈ ( 0 ..^ ( ♯ ‘ 𝐹 ) ) if- ( ( 𝑃𝑘 ) = ( 𝑃 ‘ ( 𝑘 + 1 ) ) , ( ( iEdg ‘ 𝑆 ) ‘ ( 𝐹𝑘 ) ) = { ( 𝑃𝑘 ) } , { ( 𝑃𝑘 ) , ( 𝑃 ‘ ( 𝑘 + 1 ) ) } ⊆ ( ( iEdg ‘ 𝑆 ) ‘ ( 𝐹𝑘 ) ) ) ) → ( 𝐹 ∈ Word dom ( iEdg ‘ 𝐺 ) ∧ 𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ ( Vtx ‘ 𝐺 ) ) ) )
23 3simpb ( ( 𝐹 ∈ Word dom ( iEdg ‘ 𝑆 ) ∧ 𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ ( Vtx ‘ 𝑆 ) ∧ ∀ 𝑘 ∈ ( 0 ..^ ( ♯ ‘ 𝐹 ) ) if- ( ( 𝑃𝑘 ) = ( 𝑃 ‘ ( 𝑘 + 1 ) ) , ( ( iEdg ‘ 𝑆 ) ‘ ( 𝐹𝑘 ) ) = { ( 𝑃𝑘 ) } , { ( 𝑃𝑘 ) , ( 𝑃 ‘ ( 𝑘 + 1 ) ) } ⊆ ( ( iEdg ‘ 𝑆 ) ‘ ( 𝐹𝑘 ) ) ) ) → ( 𝐹 ∈ Word dom ( iEdg ‘ 𝑆 ) ∧ ∀ 𝑘 ∈ ( 0 ..^ ( ♯ ‘ 𝐹 ) ) if- ( ( 𝑃𝑘 ) = ( 𝑃 ‘ ( 𝑘 + 1 ) ) , ( ( iEdg ‘ 𝑆 ) ‘ ( 𝐹𝑘 ) ) = { ( 𝑃𝑘 ) } , { ( 𝑃𝑘 ) , ( 𝑃 ‘ ( 𝑘 + 1 ) ) } ⊆ ( ( iEdg ‘ 𝑆 ) ‘ ( 𝐹𝑘 ) ) ) ) )
24 3 8 4 9 10 subgrprop ( 𝑆 SubGraph 𝐺 → ( ( Vtx ‘ 𝑆 ) ⊆ ( Vtx ‘ 𝐺 ) ∧ ( iEdg ‘ 𝑆 ) = ( ( iEdg ‘ 𝐺 ) ↾ dom ( iEdg ‘ 𝑆 ) ) ∧ ( Edg ‘ 𝑆 ) ⊆ 𝒫 ( Vtx ‘ 𝑆 ) ) )
25 24 simp2d ( 𝑆 SubGraph 𝐺 → ( iEdg ‘ 𝑆 ) = ( ( iEdg ‘ 𝐺 ) ↾ dom ( iEdg ‘ 𝑆 ) ) )
26 25 fveq1d ( 𝑆 SubGraph 𝐺 → ( ( iEdg ‘ 𝑆 ) ‘ ( 𝐹𝑘 ) ) = ( ( ( iEdg ‘ 𝐺 ) ↾ dom ( iEdg ‘ 𝑆 ) ) ‘ ( 𝐹𝑘 ) ) )
27 26 3ad2ant1 ( ( 𝑆 SubGraph 𝐺𝐹 ∈ Word dom ( iEdg ‘ 𝑆 ) ∧ 𝑘 ∈ ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ) → ( ( iEdg ‘ 𝑆 ) ‘ ( 𝐹𝑘 ) ) = ( ( ( iEdg ‘ 𝐺 ) ↾ dom ( iEdg ‘ 𝑆 ) ) ‘ ( 𝐹𝑘 ) ) )
28 wrdsymbcl ( ( 𝐹 ∈ Word dom ( iEdg ‘ 𝑆 ) ∧ 𝑘 ∈ ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ) → ( 𝐹𝑘 ) ∈ dom ( iEdg ‘ 𝑆 ) )
29 28 fvresd ( ( 𝐹 ∈ Word dom ( iEdg ‘ 𝑆 ) ∧ 𝑘 ∈ ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ) → ( ( ( iEdg ‘ 𝐺 ) ↾ dom ( iEdg ‘ 𝑆 ) ) ‘ ( 𝐹𝑘 ) ) = ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹𝑘 ) ) )
30 29 3adant1 ( ( 𝑆 SubGraph 𝐺𝐹 ∈ Word dom ( iEdg ‘ 𝑆 ) ∧ 𝑘 ∈ ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ) → ( ( ( iEdg ‘ 𝐺 ) ↾ dom ( iEdg ‘ 𝑆 ) ) ‘ ( 𝐹𝑘 ) ) = ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹𝑘 ) ) )
31 27 30 eqtrd ( ( 𝑆 SubGraph 𝐺𝐹 ∈ Word dom ( iEdg ‘ 𝑆 ) ∧ 𝑘 ∈ ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ) → ( ( iEdg ‘ 𝑆 ) ‘ ( 𝐹𝑘 ) ) = ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹𝑘 ) ) )
32 31 eqeq1d ( ( 𝑆 SubGraph 𝐺𝐹 ∈ Word dom ( iEdg ‘ 𝑆 ) ∧ 𝑘 ∈ ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ) → ( ( ( iEdg ‘ 𝑆 ) ‘ ( 𝐹𝑘 ) ) = { ( 𝑃𝑘 ) } ↔ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹𝑘 ) ) = { ( 𝑃𝑘 ) } ) )
33 31 sseq2d ( ( 𝑆 SubGraph 𝐺𝐹 ∈ Word dom ( iEdg ‘ 𝑆 ) ∧ 𝑘 ∈ ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ) → ( { ( 𝑃𝑘 ) , ( 𝑃 ‘ ( 𝑘 + 1 ) ) } ⊆ ( ( iEdg ‘ 𝑆 ) ‘ ( 𝐹𝑘 ) ) ↔ { ( 𝑃𝑘 ) , ( 𝑃 ‘ ( 𝑘 + 1 ) ) } ⊆ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹𝑘 ) ) ) )
34 32 33 ifpbi23d ( ( 𝑆 SubGraph 𝐺𝐹 ∈ Word dom ( iEdg ‘ 𝑆 ) ∧ 𝑘 ∈ ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ) → ( if- ( ( 𝑃𝑘 ) = ( 𝑃 ‘ ( 𝑘 + 1 ) ) , ( ( iEdg ‘ 𝑆 ) ‘ ( 𝐹𝑘 ) ) = { ( 𝑃𝑘 ) } , { ( 𝑃𝑘 ) , ( 𝑃 ‘ ( 𝑘 + 1 ) ) } ⊆ ( ( iEdg ‘ 𝑆 ) ‘ ( 𝐹𝑘 ) ) ) ↔ if- ( ( 𝑃𝑘 ) = ( 𝑃 ‘ ( 𝑘 + 1 ) ) , ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹𝑘 ) ) = { ( 𝑃𝑘 ) } , { ( 𝑃𝑘 ) , ( 𝑃 ‘ ( 𝑘 + 1 ) ) } ⊆ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹𝑘 ) ) ) ) )
35 34 biimpd ( ( 𝑆 SubGraph 𝐺𝐹 ∈ Word dom ( iEdg ‘ 𝑆 ) ∧ 𝑘 ∈ ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ) → ( if- ( ( 𝑃𝑘 ) = ( 𝑃 ‘ ( 𝑘 + 1 ) ) , ( ( iEdg ‘ 𝑆 ) ‘ ( 𝐹𝑘 ) ) = { ( 𝑃𝑘 ) } , { ( 𝑃𝑘 ) , ( 𝑃 ‘ ( 𝑘 + 1 ) ) } ⊆ ( ( iEdg ‘ 𝑆 ) ‘ ( 𝐹𝑘 ) ) ) → if- ( ( 𝑃𝑘 ) = ( 𝑃 ‘ ( 𝑘 + 1 ) ) , ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹𝑘 ) ) = { ( 𝑃𝑘 ) } , { ( 𝑃𝑘 ) , ( 𝑃 ‘ ( 𝑘 + 1 ) ) } ⊆ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹𝑘 ) ) ) ) )
36 35 3expia ( ( 𝑆 SubGraph 𝐺𝐹 ∈ Word dom ( iEdg ‘ 𝑆 ) ) → ( 𝑘 ∈ ( 0 ..^ ( ♯ ‘ 𝐹 ) ) → ( if- ( ( 𝑃𝑘 ) = ( 𝑃 ‘ ( 𝑘 + 1 ) ) , ( ( iEdg ‘ 𝑆 ) ‘ ( 𝐹𝑘 ) ) = { ( 𝑃𝑘 ) } , { ( 𝑃𝑘 ) , ( 𝑃 ‘ ( 𝑘 + 1 ) ) } ⊆ ( ( iEdg ‘ 𝑆 ) ‘ ( 𝐹𝑘 ) ) ) → if- ( ( 𝑃𝑘 ) = ( 𝑃 ‘ ( 𝑘 + 1 ) ) , ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹𝑘 ) ) = { ( 𝑃𝑘 ) } , { ( 𝑃𝑘 ) , ( 𝑃 ‘ ( 𝑘 + 1 ) ) } ⊆ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹𝑘 ) ) ) ) ) )
37 36 ralrimiv ( ( 𝑆 SubGraph 𝐺𝐹 ∈ Word dom ( iEdg ‘ 𝑆 ) ) → ∀ 𝑘 ∈ ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ( if- ( ( 𝑃𝑘 ) = ( 𝑃 ‘ ( 𝑘 + 1 ) ) , ( ( iEdg ‘ 𝑆 ) ‘ ( 𝐹𝑘 ) ) = { ( 𝑃𝑘 ) } , { ( 𝑃𝑘 ) , ( 𝑃 ‘ ( 𝑘 + 1 ) ) } ⊆ ( ( iEdg ‘ 𝑆 ) ‘ ( 𝐹𝑘 ) ) ) → if- ( ( 𝑃𝑘 ) = ( 𝑃 ‘ ( 𝑘 + 1 ) ) , ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹𝑘 ) ) = { ( 𝑃𝑘 ) } , { ( 𝑃𝑘 ) , ( 𝑃 ‘ ( 𝑘 + 1 ) ) } ⊆ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹𝑘 ) ) ) ) )
38 ralim ( ∀ 𝑘 ∈ ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ( if- ( ( 𝑃𝑘 ) = ( 𝑃 ‘ ( 𝑘 + 1 ) ) , ( ( iEdg ‘ 𝑆 ) ‘ ( 𝐹𝑘 ) ) = { ( 𝑃𝑘 ) } , { ( 𝑃𝑘 ) , ( 𝑃 ‘ ( 𝑘 + 1 ) ) } ⊆ ( ( iEdg ‘ 𝑆 ) ‘ ( 𝐹𝑘 ) ) ) → if- ( ( 𝑃𝑘 ) = ( 𝑃 ‘ ( 𝑘 + 1 ) ) , ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹𝑘 ) ) = { ( 𝑃𝑘 ) } , { ( 𝑃𝑘 ) , ( 𝑃 ‘ ( 𝑘 + 1 ) ) } ⊆ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹𝑘 ) ) ) ) → ( ∀ 𝑘 ∈ ( 0 ..^ ( ♯ ‘ 𝐹 ) ) if- ( ( 𝑃𝑘 ) = ( 𝑃 ‘ ( 𝑘 + 1 ) ) , ( ( iEdg ‘ 𝑆 ) ‘ ( 𝐹𝑘 ) ) = { ( 𝑃𝑘 ) } , { ( 𝑃𝑘 ) , ( 𝑃 ‘ ( 𝑘 + 1 ) ) } ⊆ ( ( iEdg ‘ 𝑆 ) ‘ ( 𝐹𝑘 ) ) ) → ∀ 𝑘 ∈ ( 0 ..^ ( ♯ ‘ 𝐹 ) ) if- ( ( 𝑃𝑘 ) = ( 𝑃 ‘ ( 𝑘 + 1 ) ) , ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹𝑘 ) ) = { ( 𝑃𝑘 ) } , { ( 𝑃𝑘 ) , ( 𝑃 ‘ ( 𝑘 + 1 ) ) } ⊆ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹𝑘 ) ) ) ) )
39 37 38 syl ( ( 𝑆 SubGraph 𝐺𝐹 ∈ Word dom ( iEdg ‘ 𝑆 ) ) → ( ∀ 𝑘 ∈ ( 0 ..^ ( ♯ ‘ 𝐹 ) ) if- ( ( 𝑃𝑘 ) = ( 𝑃 ‘ ( 𝑘 + 1 ) ) , ( ( iEdg ‘ 𝑆 ) ‘ ( 𝐹𝑘 ) ) = { ( 𝑃𝑘 ) } , { ( 𝑃𝑘 ) , ( 𝑃 ‘ ( 𝑘 + 1 ) ) } ⊆ ( ( iEdg ‘ 𝑆 ) ‘ ( 𝐹𝑘 ) ) ) → ∀ 𝑘 ∈ ( 0 ..^ ( ♯ ‘ 𝐹 ) ) if- ( ( 𝑃𝑘 ) = ( 𝑃 ‘ ( 𝑘 + 1 ) ) , ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹𝑘 ) ) = { ( 𝑃𝑘 ) } , { ( 𝑃𝑘 ) , ( 𝑃 ‘ ( 𝑘 + 1 ) ) } ⊆ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹𝑘 ) ) ) ) )
40 39 expimpd ( 𝑆 SubGraph 𝐺 → ( ( 𝐹 ∈ Word dom ( iEdg ‘ 𝑆 ) ∧ ∀ 𝑘 ∈ ( 0 ..^ ( ♯ ‘ 𝐹 ) ) if- ( ( 𝑃𝑘 ) = ( 𝑃 ‘ ( 𝑘 + 1 ) ) , ( ( iEdg ‘ 𝑆 ) ‘ ( 𝐹𝑘 ) ) = { ( 𝑃𝑘 ) } , { ( 𝑃𝑘 ) , ( 𝑃 ‘ ( 𝑘 + 1 ) ) } ⊆ ( ( iEdg ‘ 𝑆 ) ‘ ( 𝐹𝑘 ) ) ) ) → ∀ 𝑘 ∈ ( 0 ..^ ( ♯ ‘ 𝐹 ) ) if- ( ( 𝑃𝑘 ) = ( 𝑃 ‘ ( 𝑘 + 1 ) ) , ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹𝑘 ) ) = { ( 𝑃𝑘 ) } , { ( 𝑃𝑘 ) , ( 𝑃 ‘ ( 𝑘 + 1 ) ) } ⊆ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹𝑘 ) ) ) ) )
41 23 40 syl5 ( 𝑆 SubGraph 𝐺 → ( ( 𝐹 ∈ Word dom ( iEdg ‘ 𝑆 ) ∧ 𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ ( Vtx ‘ 𝑆 ) ∧ ∀ 𝑘 ∈ ( 0 ..^ ( ♯ ‘ 𝐹 ) ) if- ( ( 𝑃𝑘 ) = ( 𝑃 ‘ ( 𝑘 + 1 ) ) , ( ( iEdg ‘ 𝑆 ) ‘ ( 𝐹𝑘 ) ) = { ( 𝑃𝑘 ) } , { ( 𝑃𝑘 ) , ( 𝑃 ‘ ( 𝑘 + 1 ) ) } ⊆ ( ( iEdg ‘ 𝑆 ) ‘ ( 𝐹𝑘 ) ) ) ) → ∀ 𝑘 ∈ ( 0 ..^ ( ♯ ‘ 𝐹 ) ) if- ( ( 𝑃𝑘 ) = ( 𝑃 ‘ ( 𝑘 + 1 ) ) , ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹𝑘 ) ) = { ( 𝑃𝑘 ) } , { ( 𝑃𝑘 ) , ( 𝑃 ‘ ( 𝑘 + 1 ) ) } ⊆ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹𝑘 ) ) ) ) )
42 22 41 jcad ( 𝑆 SubGraph 𝐺 → ( ( 𝐹 ∈ Word dom ( iEdg ‘ 𝑆 ) ∧ 𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ ( Vtx ‘ 𝑆 ) ∧ ∀ 𝑘 ∈ ( 0 ..^ ( ♯ ‘ 𝐹 ) ) if- ( ( 𝑃𝑘 ) = ( 𝑃 ‘ ( 𝑘 + 1 ) ) , ( ( iEdg ‘ 𝑆 ) ‘ ( 𝐹𝑘 ) ) = { ( 𝑃𝑘 ) } , { ( 𝑃𝑘 ) , ( 𝑃 ‘ ( 𝑘 + 1 ) ) } ⊆ ( ( iEdg ‘ 𝑆 ) ‘ ( 𝐹𝑘 ) ) ) ) → ( ( 𝐹 ∈ Word dom ( iEdg ‘ 𝐺 ) ∧ 𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ ( Vtx ‘ 𝐺 ) ) ∧ ∀ 𝑘 ∈ ( 0 ..^ ( ♯ ‘ 𝐹 ) ) if- ( ( 𝑃𝑘 ) = ( 𝑃 ‘ ( 𝑘 + 1 ) ) , ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹𝑘 ) ) = { ( 𝑃𝑘 ) } , { ( 𝑃𝑘 ) , ( 𝑃 ‘ ( 𝑘 + 1 ) ) } ⊆ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹𝑘 ) ) ) ) ) )
43 6 42 sylbid ( 𝑆 SubGraph 𝐺 → ( 𝐹 ( Walks ‘ 𝑆 ) 𝑃 → ( ( 𝐹 ∈ Word dom ( iEdg ‘ 𝐺 ) ∧ 𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ ( Vtx ‘ 𝐺 ) ) ∧ ∀ 𝑘 ∈ ( 0 ..^ ( ♯ ‘ 𝐹 ) ) if- ( ( 𝑃𝑘 ) = ( 𝑃 ‘ ( 𝑘 + 1 ) ) , ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹𝑘 ) ) = { ( 𝑃𝑘 ) } , { ( 𝑃𝑘 ) , ( 𝑃 ‘ ( 𝑘 + 1 ) ) } ⊆ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹𝑘 ) ) ) ) ) )
44 df-3an ( ( 𝐹 ∈ Word dom ( iEdg ‘ 𝐺 ) ∧ 𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ ( Vtx ‘ 𝐺 ) ∧ ∀ 𝑘 ∈ ( 0 ..^ ( ♯ ‘ 𝐹 ) ) if- ( ( 𝑃𝑘 ) = ( 𝑃 ‘ ( 𝑘 + 1 ) ) , ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹𝑘 ) ) = { ( 𝑃𝑘 ) } , { ( 𝑃𝑘 ) , ( 𝑃 ‘ ( 𝑘 + 1 ) ) } ⊆ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹𝑘 ) ) ) ) ↔ ( ( 𝐹 ∈ Word dom ( iEdg ‘ 𝐺 ) ∧ 𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ ( Vtx ‘ 𝐺 ) ) ∧ ∀ 𝑘 ∈ ( 0 ..^ ( ♯ ‘ 𝐹 ) ) if- ( ( 𝑃𝑘 ) = ( 𝑃 ‘ ( 𝑘 + 1 ) ) , ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹𝑘 ) ) = { ( 𝑃𝑘 ) } , { ( 𝑃𝑘 ) , ( 𝑃 ‘ ( 𝑘 + 1 ) ) } ⊆ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹𝑘 ) ) ) ) )
45 43 44 syl6ibr ( 𝑆 SubGraph 𝐺 → ( 𝐹 ( Walks ‘ 𝑆 ) 𝑃 → ( 𝐹 ∈ Word dom ( iEdg ‘ 𝐺 ) ∧ 𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ ( Vtx ‘ 𝐺 ) ∧ ∀ 𝑘 ∈ ( 0 ..^ ( ♯ ‘ 𝐹 ) ) if- ( ( 𝑃𝑘 ) = ( 𝑃 ‘ ( 𝑘 + 1 ) ) , ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹𝑘 ) ) = { ( 𝑃𝑘 ) } , { ( 𝑃𝑘 ) , ( 𝑃 ‘ ( 𝑘 + 1 ) ) } ⊆ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹𝑘 ) ) ) ) ) )
46 8 9 iswlkg ( 𝐺 ∈ V → ( 𝐹 ( Walks ‘ 𝐺 ) 𝑃 ↔ ( 𝐹 ∈ Word dom ( iEdg ‘ 𝐺 ) ∧ 𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ ( Vtx ‘ 𝐺 ) ∧ ∀ 𝑘 ∈ ( 0 ..^ ( ♯ ‘ 𝐹 ) ) if- ( ( 𝑃𝑘 ) = ( 𝑃 ‘ ( 𝑘 + 1 ) ) , ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹𝑘 ) ) = { ( 𝑃𝑘 ) } , { ( 𝑃𝑘 ) , ( 𝑃 ‘ ( 𝑘 + 1 ) ) } ⊆ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹𝑘 ) ) ) ) ) )
47 1 46 simpl2im ( 𝑆 SubGraph 𝐺 → ( 𝐹 ( Walks ‘ 𝐺 ) 𝑃 ↔ ( 𝐹 ∈ Word dom ( iEdg ‘ 𝐺 ) ∧ 𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ ( Vtx ‘ 𝐺 ) ∧ ∀ 𝑘 ∈ ( 0 ..^ ( ♯ ‘ 𝐹 ) ) if- ( ( 𝑃𝑘 ) = ( 𝑃 ‘ ( 𝑘 + 1 ) ) , ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹𝑘 ) ) = { ( 𝑃𝑘 ) } , { ( 𝑃𝑘 ) , ( 𝑃 ‘ ( 𝑘 + 1 ) ) } ⊆ ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹𝑘 ) ) ) ) ) )
48 45 47 sylibrd ( 𝑆 SubGraph 𝐺 → ( 𝐹 ( Walks ‘ 𝑆 ) 𝑃𝐹 ( Walks ‘ 𝐺 ) 𝑃 ) )