Metamath Proof Explorer

Theorem clwwlknp

Description: Properties of a set being a closed walk (represented by a word). (Contributed by Alexander van der Vekens, 17-Jun-2018) (Revised by AV, 24-Apr-2021) (Proof shortened by AV, 23-Mar-2022)

Ref Expression
Hypotheses isclwwlknx.v ⊢ 𝑉 = ( Vtx ‘ 𝐺 )
isclwwlknx.e ⊢ 𝐸 = ( Edg ‘ 𝐺 )
Assertion clwwlknp ( 𝑊 ∈ ( 𝑁 ClWWalksN 𝐺 ) → ( ( 𝑊 ∈ Word 𝑉 ∧ ( ♯ ‘ 𝑊 ) = 𝑁 ) ∧ ∀ 𝑖 ∈ ( 0 ..^ ( 𝑁 − 1 ) ) { ( 𝑊 ‘ 𝑖 ) , ( 𝑊 ‘ ( 𝑖 + 1 ) ) } ∈ 𝐸 ∧ { ( lastS ‘ 𝑊 ) , ( 𝑊 ‘ 0 ) } ∈ 𝐸 ) )

Proof

Step Hyp Ref Expression
1 isclwwlknx.v ⊢ 𝑉 = ( Vtx ‘ 𝐺 )
2 isclwwlknx.e ⊢ 𝐸 = ( Edg ‘ 𝐺 )
3 1 clwwlknbp ⊢ ( 𝑊 ∈ ( 𝑁 ClWWalksN 𝐺 ) → ( 𝑊 ∈ Word 𝑉 ∧ ( ♯ ‘ 𝑊 ) = 𝑁 ) )
4 simpr ⊢ ( ( 𝑊 ∈ ( 𝑁 ClWWalksN 𝐺 ) ∧ ( 𝑊 ∈ Word 𝑉 ∧ ( ♯ ‘ 𝑊 ) = 𝑁 ) ) → ( 𝑊 ∈ Word 𝑉 ∧ ( ♯ ‘ 𝑊 ) = 𝑁 ) )
5 clwwlknnn ⊢ ( 𝑊 ∈ ( 𝑁 ClWWalksN 𝐺 ) → 𝑁 ∈ ℕ )
6 1 2 isclwwlknx ⊢ ( 𝑁 ∈ ℕ → ( 𝑊 ∈ ( 𝑁 ClWWalksN 𝐺 ) ↔ ( ( 𝑊 ∈ Word 𝑉 ∧ ∀ 𝑖 ∈ ( 0 ..^ ( ( ♯ ‘ 𝑊 ) − 1 ) ) { ( 𝑊 ‘ 𝑖 ) , ( 𝑊 ‘ ( 𝑖 + 1 ) ) } ∈ 𝐸 ∧ { ( lastS ‘ 𝑊 ) , ( 𝑊 ‘ 0 ) } ∈ 𝐸 ) ∧ ( ♯ ‘ 𝑊 ) = 𝑁 ) ) )
7 3simpc ⊢ ( ( 𝑊 ∈ Word 𝑉 ∧ ∀ 𝑖 ∈ ( 0 ..^ ( ( ♯ ‘ 𝑊 ) − 1 ) ) { ( 𝑊 ‘ 𝑖 ) , ( 𝑊 ‘ ( 𝑖 + 1 ) ) } ∈ 𝐸 ∧ { ( lastS ‘ 𝑊 ) , ( 𝑊 ‘ 0 ) } ∈ 𝐸 ) → ( ∀ 𝑖 ∈ ( 0 ..^ ( ( ♯ ‘ 𝑊 ) − 1 ) ) { ( 𝑊 ‘ 𝑖 ) , ( 𝑊 ‘ ( 𝑖 + 1 ) ) } ∈ 𝐸 ∧ { ( lastS ‘ 𝑊 ) , ( 𝑊 ‘ 0 ) } ∈ 𝐸 ) )
8 7 adantr ⊢ ( ( ( 𝑊 ∈ Word 𝑉 ∧ ∀ 𝑖 ∈ ( 0 ..^ ( ( ♯ ‘ 𝑊 ) − 1 ) ) { ( 𝑊 ‘ 𝑖 ) , ( 𝑊 ‘ ( 𝑖 + 1 ) ) } ∈ 𝐸 ∧ { ( lastS ‘ 𝑊 ) , ( 𝑊 ‘ 0 ) } ∈ 𝐸 ) ∧ ( ♯ ‘ 𝑊 ) = 𝑁 ) → ( ∀ 𝑖 ∈ ( 0 ..^ ( ( ♯ ‘ 𝑊 ) − 1 ) ) { ( 𝑊 ‘ 𝑖 ) , ( 𝑊 ‘ ( 𝑖 + 1 ) ) } ∈ 𝐸 ∧ { ( lastS ‘ 𝑊 ) , ( 𝑊 ‘ 0 ) } ∈ 𝐸 ) )
9 6 8 syl6bi ⊢ ( 𝑁 ∈ ℕ → ( 𝑊 ∈ ( 𝑁 ClWWalksN 𝐺 ) → ( ∀ 𝑖 ∈ ( 0 ..^ ( ( ♯ ‘ 𝑊 ) − 1 ) ) { ( 𝑊 ‘ 𝑖 ) , ( 𝑊 ‘ ( 𝑖 + 1 ) ) } ∈ 𝐸 ∧ { ( lastS ‘ 𝑊 ) , ( 𝑊 ‘ 0 ) } ∈ 𝐸 ) ) )
10 5 9 mpcom ⊢ ( 𝑊 ∈ ( 𝑁 ClWWalksN 𝐺 ) → ( ∀ 𝑖 ∈ ( 0 ..^ ( ( ♯ ‘ 𝑊 ) − 1 ) ) { ( 𝑊 ‘ 𝑖 ) , ( 𝑊 ‘ ( 𝑖 + 1 ) ) } ∈ 𝐸 ∧ { ( lastS ‘ 𝑊 ) , ( 𝑊 ‘ 0 ) } ∈ 𝐸 ) )
11 10 adantr ⊢ ( ( 𝑊 ∈ ( 𝑁 ClWWalksN 𝐺 ) ∧ ( 𝑊 ∈ Word 𝑉 ∧ ( ♯ ‘ 𝑊 ) = 𝑁 ) ) → ( ∀ 𝑖 ∈ ( 0 ..^ ( ( ♯ ‘ 𝑊 ) − 1 ) ) { ( 𝑊 ‘ 𝑖 ) , ( 𝑊 ‘ ( 𝑖 + 1 ) ) } ∈ 𝐸 ∧ { ( lastS ‘ 𝑊 ) , ( 𝑊 ‘ 0 ) } ∈ 𝐸 ) )
12 oveq1 ⊢ ( ( ♯ ‘ 𝑊 ) = 𝑁 → ( ( ♯ ‘ 𝑊 ) − 1 ) = ( 𝑁 − 1 ) )
13 12 oveq2d ⊢ ( ( ♯ ‘ 𝑊 ) = 𝑁 → ( 0 ..^ ( ( ♯ ‘ 𝑊 ) − 1 ) ) = ( 0 ..^ ( 𝑁 − 1 ) ) )
14 13 raleqdv ⊢ ( ( ♯ ‘ 𝑊 ) = 𝑁 → ( ∀ 𝑖 ∈ ( 0 ..^ ( ( ♯ ‘ 𝑊 ) − 1 ) ) { ( 𝑊 ‘ 𝑖 ) , ( 𝑊 ‘ ( 𝑖 + 1 ) ) } ∈ 𝐸 ↔ ∀ 𝑖 ∈ ( 0 ..^ ( 𝑁 − 1 ) ) { ( 𝑊 ‘ 𝑖 ) , ( 𝑊 ‘ ( 𝑖 + 1 ) ) } ∈ 𝐸 ) )
15 14 anbi1d ⊢ ( ( ♯ ‘ 𝑊 ) = 𝑁 → ( ( ∀ 𝑖 ∈ ( 0 ..^ ( ( ♯ ‘ 𝑊 ) − 1 ) ) { ( 𝑊 ‘ 𝑖 ) , ( 𝑊 ‘ ( 𝑖 + 1 ) ) } ∈ 𝐸 ∧ { ( lastS ‘ 𝑊 ) , ( 𝑊 ‘ 0 ) } ∈ 𝐸 ) ↔ ( ∀ 𝑖 ∈ ( 0 ..^ ( 𝑁 − 1 ) ) { ( 𝑊 ‘ 𝑖 ) , ( 𝑊 ‘ ( 𝑖 + 1 ) ) } ∈ 𝐸 ∧ { ( lastS ‘ 𝑊 ) , ( 𝑊 ‘ 0 ) } ∈ 𝐸 ) ) )
16 15 ad2antll ⊢ ( ( 𝑊 ∈ ( 𝑁 ClWWalksN 𝐺 ) ∧ ( 𝑊 ∈ Word 𝑉 ∧ ( ♯ ‘ 𝑊 ) = 𝑁 ) ) → ( ( ∀ 𝑖 ∈ ( 0 ..^ ( ( ♯ ‘ 𝑊 ) − 1 ) ) { ( 𝑊 ‘ 𝑖 ) , ( 𝑊 ‘ ( 𝑖 + 1 ) ) } ∈ 𝐸 ∧ { ( lastS ‘ 𝑊 ) , ( 𝑊 ‘ 0 ) } ∈ 𝐸 ) ↔ ( ∀ 𝑖 ∈ ( 0 ..^ ( 𝑁 − 1 ) ) { ( 𝑊 ‘ 𝑖 ) , ( 𝑊 ‘ ( 𝑖 + 1 ) ) } ∈ 𝐸 ∧ { ( lastS ‘ 𝑊 ) , ( 𝑊 ‘ 0 ) } ∈ 𝐸 ) ) )
17 11 16 mpbid ⊢ ( ( 𝑊 ∈ ( 𝑁 ClWWalksN 𝐺 ) ∧ ( 𝑊 ∈ Word 𝑉 ∧ ( ♯ ‘ 𝑊 ) = 𝑁 ) ) → ( ∀ 𝑖 ∈ ( 0 ..^ ( 𝑁 − 1 ) ) { ( 𝑊 ‘ 𝑖 ) , ( 𝑊 ‘ ( 𝑖 + 1 ) ) } ∈ 𝐸 ∧ { ( lastS ‘ 𝑊 ) , ( 𝑊 ‘ 0 ) } ∈ 𝐸 ) )
18 4 17 jca ⊢ ( ( 𝑊 ∈ ( 𝑁 ClWWalksN 𝐺 ) ∧ ( 𝑊 ∈ Word 𝑉 ∧ ( ♯ ‘ 𝑊 ) = 𝑁 ) ) → ( ( 𝑊 ∈ Word 𝑉 ∧ ( ♯ ‘ 𝑊 ) = 𝑁 ) ∧ ( ∀ 𝑖 ∈ ( 0 ..^ ( 𝑁 − 1 ) ) { ( 𝑊 ‘ 𝑖 ) , ( 𝑊 ‘ ( 𝑖 + 1 ) ) } ∈ 𝐸 ∧ { ( lastS ‘ 𝑊 ) , ( 𝑊 ‘ 0 ) } ∈ 𝐸 ) ) )
19 3 18 mpdan ⊢ ( 𝑊 ∈ ( 𝑁 ClWWalksN 𝐺 ) → ( ( 𝑊 ∈ Word 𝑉 ∧ ( ♯ ‘ 𝑊 ) = 𝑁 ) ∧ ( ∀ 𝑖 ∈ ( 0 ..^ ( 𝑁 − 1 ) ) { ( 𝑊 ‘ 𝑖 ) , ( 𝑊 ‘ ( 𝑖 + 1 ) ) } ∈ 𝐸 ∧ { ( lastS ‘ 𝑊 ) , ( 𝑊 ‘ 0 ) } ∈ 𝐸 ) ) )
20 3anass ⊢ ( ( ( 𝑊 ∈ Word 𝑉 ∧ ( ♯ ‘ 𝑊 ) = 𝑁 ) ∧ ∀ 𝑖 ∈ ( 0 ..^ ( 𝑁 − 1 ) ) { ( 𝑊 ‘ 𝑖 ) , ( 𝑊 ‘ ( 𝑖 + 1 ) ) } ∈ 𝐸 ∧ { ( lastS ‘ 𝑊 ) , ( 𝑊 ‘ 0 ) } ∈ 𝐸 ) ↔ ( ( 𝑊 ∈ Word 𝑉 ∧ ( ♯ ‘ 𝑊 ) = 𝑁 ) ∧ ( ∀ 𝑖 ∈ ( 0 ..^ ( 𝑁 − 1 ) ) { ( 𝑊 ‘ 𝑖 ) , ( 𝑊 ‘ ( 𝑖 + 1 ) ) } ∈ 𝐸 ∧ { ( lastS ‘ 𝑊 ) , ( 𝑊 ‘ 0 ) } ∈ 𝐸 ) ) )
21 19 20 sylibr ⊢ ( 𝑊 ∈ ( 𝑁 ClWWalksN 𝐺 ) → ( ( 𝑊 ∈ Word 𝑉 ∧ ( ♯ ‘ 𝑊 ) = 𝑁 ) ∧ ∀ 𝑖 ∈ ( 0 ..^ ( 𝑁 − 1 ) ) { ( 𝑊 ‘ 𝑖 ) , ( 𝑊 ‘ ( 𝑖 + 1 ) ) } ∈ 𝐸 ∧ { ( lastS ‘ 𝑊 ) , ( 𝑊 ‘ 0 ) } ∈ 𝐸 ) )