| Step | Hyp | Ref | Expression | 
|---|
| 1 |  | neeq1 3002 | . . . 4
⊢ (𝑤 = 𝑊 → (𝑤 ≠ ∅ ↔ 𝑊 ≠ ∅)) | 
| 2 |  | fveq2 6905 | . . . . . . 7
⊢ (𝑤 = 𝑊 → (♯‘𝑤) = (♯‘𝑊)) | 
| 3 | 2 | oveq1d 7447 | . . . . . 6
⊢ (𝑤 = 𝑊 → ((♯‘𝑤) − 1) = ((♯‘𝑊) − 1)) | 
| 4 | 3 | oveq2d 7448 | . . . . 5
⊢ (𝑤 = 𝑊 → (0..^((♯‘𝑤) − 1)) =
(0..^((♯‘𝑊)
− 1))) | 
| 5 |  | fveq1 6904 | . . . . . . 7
⊢ (𝑤 = 𝑊 → (𝑤‘𝑖) = (𝑊‘𝑖)) | 
| 6 |  | fveq1 6904 | . . . . . . 7
⊢ (𝑤 = 𝑊 → (𝑤‘(𝑖 + 1)) = (𝑊‘(𝑖 + 1))) | 
| 7 | 5, 6 | preq12d 4740 | . . . . . 6
⊢ (𝑤 = 𝑊 → {(𝑤‘𝑖), (𝑤‘(𝑖 + 1))} = {(𝑊‘𝑖), (𝑊‘(𝑖 + 1))}) | 
| 8 | 7 | eleq1d 2825 | . . . . 5
⊢ (𝑤 = 𝑊 → ({(𝑤‘𝑖), (𝑤‘(𝑖 + 1))} ∈ 𝐸 ↔ {(𝑊‘𝑖), (𝑊‘(𝑖 + 1))} ∈ 𝐸)) | 
| 9 | 4, 8 | raleqbidv 3345 | . . . 4
⊢ (𝑤 = 𝑊 → (∀𝑖 ∈ (0..^((♯‘𝑤) − 1)){(𝑤‘𝑖), (𝑤‘(𝑖 + 1))} ∈ 𝐸 ↔ ∀𝑖 ∈ (0..^((♯‘𝑊) − 1)){(𝑊‘𝑖), (𝑊‘(𝑖 + 1))} ∈ 𝐸)) | 
| 10 |  | fveq2 6905 | . . . . . 6
⊢ (𝑤 = 𝑊 → (lastS‘𝑤) = (lastS‘𝑊)) | 
| 11 |  | fveq1 6904 | . . . . . 6
⊢ (𝑤 = 𝑊 → (𝑤‘0) = (𝑊‘0)) | 
| 12 | 10, 11 | preq12d 4740 | . . . . 5
⊢ (𝑤 = 𝑊 → {(lastS‘𝑤), (𝑤‘0)} = {(lastS‘𝑊), (𝑊‘0)}) | 
| 13 | 12 | eleq1d 2825 | . . . 4
⊢ (𝑤 = 𝑊 → ({(lastS‘𝑤), (𝑤‘0)} ∈ 𝐸 ↔ {(lastS‘𝑊), (𝑊‘0)} ∈ 𝐸)) | 
| 14 | 1, 9, 13 | 3anbi123d 1437 | . . 3
⊢ (𝑤 = 𝑊 → ((𝑤 ≠ ∅ ∧ ∀𝑖 ∈
(0..^((♯‘𝑤)
− 1)){(𝑤‘𝑖), (𝑤‘(𝑖 + 1))} ∈ 𝐸 ∧ {(lastS‘𝑤), (𝑤‘0)} ∈ 𝐸) ↔ (𝑊 ≠ ∅ ∧ ∀𝑖 ∈
(0..^((♯‘𝑊)
− 1)){(𝑊‘𝑖), (𝑊‘(𝑖 + 1))} ∈ 𝐸 ∧ {(lastS‘𝑊), (𝑊‘0)} ∈ 𝐸))) | 
| 15 | 14 | elrab 3691 | . 2
⊢ (𝑊 ∈ {𝑤 ∈ Word 𝑉 ∣ (𝑤 ≠ ∅ ∧ ∀𝑖 ∈
(0..^((♯‘𝑤)
− 1)){(𝑤‘𝑖), (𝑤‘(𝑖 + 1))} ∈ 𝐸 ∧ {(lastS‘𝑤), (𝑤‘0)} ∈ 𝐸)} ↔ (𝑊 ∈ Word 𝑉 ∧ (𝑊 ≠ ∅ ∧ ∀𝑖 ∈
(0..^((♯‘𝑊)
− 1)){(𝑊‘𝑖), (𝑊‘(𝑖 + 1))} ∈ 𝐸 ∧ {(lastS‘𝑊), (𝑊‘0)} ∈ 𝐸))) | 
| 16 |  | clwwlk.v | . . . 4
⊢ 𝑉 = (Vtx‘𝐺) | 
| 17 |  | clwwlk.e | . . . 4
⊢ 𝐸 = (Edg‘𝐺) | 
| 18 | 16, 17 | clwwlk 30003 | . . 3
⊢
(ClWWalks‘𝐺) =
{𝑤 ∈ Word 𝑉 ∣ (𝑤 ≠ ∅ ∧ ∀𝑖 ∈
(0..^((♯‘𝑤)
− 1)){(𝑤‘𝑖), (𝑤‘(𝑖 + 1))} ∈ 𝐸 ∧ {(lastS‘𝑤), (𝑤‘0)} ∈ 𝐸)} | 
| 19 | 18 | eleq2i 2832 | . 2
⊢ (𝑊 ∈ (ClWWalks‘𝐺) ↔ 𝑊 ∈ {𝑤 ∈ Word 𝑉 ∣ (𝑤 ≠ ∅ ∧ ∀𝑖 ∈
(0..^((♯‘𝑤)
− 1)){(𝑤‘𝑖), (𝑤‘(𝑖 + 1))} ∈ 𝐸 ∧ {(lastS‘𝑤), (𝑤‘0)} ∈ 𝐸)}) | 
| 20 |  | 3anass 1094 | . . 3
⊢ (((𝑊 ∈ Word 𝑉 ∧ 𝑊 ≠ ∅) ∧ ∀𝑖 ∈
(0..^((♯‘𝑊)
− 1)){(𝑊‘𝑖), (𝑊‘(𝑖 + 1))} ∈ 𝐸 ∧ {(lastS‘𝑊), (𝑊‘0)} ∈ 𝐸) ↔ ((𝑊 ∈ Word 𝑉 ∧ 𝑊 ≠ ∅) ∧ (∀𝑖 ∈
(0..^((♯‘𝑊)
− 1)){(𝑊‘𝑖), (𝑊‘(𝑖 + 1))} ∈ 𝐸 ∧ {(lastS‘𝑊), (𝑊‘0)} ∈ 𝐸))) | 
| 21 |  | anass 468 | . . 3
⊢ (((𝑊 ∈ Word 𝑉 ∧ 𝑊 ≠ ∅) ∧ (∀𝑖 ∈
(0..^((♯‘𝑊)
− 1)){(𝑊‘𝑖), (𝑊‘(𝑖 + 1))} ∈ 𝐸 ∧ {(lastS‘𝑊), (𝑊‘0)} ∈ 𝐸)) ↔ (𝑊 ∈ Word 𝑉 ∧ (𝑊 ≠ ∅ ∧ (∀𝑖 ∈
(0..^((♯‘𝑊)
− 1)){(𝑊‘𝑖), (𝑊‘(𝑖 + 1))} ∈ 𝐸 ∧ {(lastS‘𝑊), (𝑊‘0)} ∈ 𝐸)))) | 
| 22 |  | 3anass 1094 | . . . . 5
⊢ ((𝑊 ≠ ∅ ∧
∀𝑖 ∈
(0..^((♯‘𝑊)
− 1)){(𝑊‘𝑖), (𝑊‘(𝑖 + 1))} ∈ 𝐸 ∧ {(lastS‘𝑊), (𝑊‘0)} ∈ 𝐸) ↔ (𝑊 ≠ ∅ ∧ (∀𝑖 ∈
(0..^((♯‘𝑊)
− 1)){(𝑊‘𝑖), (𝑊‘(𝑖 + 1))} ∈ 𝐸 ∧ {(lastS‘𝑊), (𝑊‘0)} ∈ 𝐸))) | 
| 23 | 22 | bicomi 224 | . . . 4
⊢ ((𝑊 ≠ ∅ ∧
(∀𝑖 ∈
(0..^((♯‘𝑊)
− 1)){(𝑊‘𝑖), (𝑊‘(𝑖 + 1))} ∈ 𝐸 ∧ {(lastS‘𝑊), (𝑊‘0)} ∈ 𝐸)) ↔ (𝑊 ≠ ∅ ∧ ∀𝑖 ∈
(0..^((♯‘𝑊)
− 1)){(𝑊‘𝑖), (𝑊‘(𝑖 + 1))} ∈ 𝐸 ∧ {(lastS‘𝑊), (𝑊‘0)} ∈ 𝐸)) | 
| 24 | 23 | anbi2i 623 | . . 3
⊢ ((𝑊 ∈ Word 𝑉 ∧ (𝑊 ≠ ∅ ∧ (∀𝑖 ∈
(0..^((♯‘𝑊)
− 1)){(𝑊‘𝑖), (𝑊‘(𝑖 + 1))} ∈ 𝐸 ∧ {(lastS‘𝑊), (𝑊‘0)} ∈ 𝐸))) ↔ (𝑊 ∈ Word 𝑉 ∧ (𝑊 ≠ ∅ ∧ ∀𝑖 ∈
(0..^((♯‘𝑊)
− 1)){(𝑊‘𝑖), (𝑊‘(𝑖 + 1))} ∈ 𝐸 ∧ {(lastS‘𝑊), (𝑊‘0)} ∈ 𝐸))) | 
| 25 | 20, 21, 24 | 3bitri 297 | . 2
⊢ (((𝑊 ∈ Word 𝑉 ∧ 𝑊 ≠ ∅) ∧ ∀𝑖 ∈
(0..^((♯‘𝑊)
− 1)){(𝑊‘𝑖), (𝑊‘(𝑖 + 1))} ∈ 𝐸 ∧ {(lastS‘𝑊), (𝑊‘0)} ∈ 𝐸) ↔ (𝑊 ∈ Word 𝑉 ∧ (𝑊 ≠ ∅ ∧ ∀𝑖 ∈
(0..^((♯‘𝑊)
− 1)){(𝑊‘𝑖), (𝑊‘(𝑖 + 1))} ∈ 𝐸 ∧ {(lastS‘𝑊), (𝑊‘0)} ∈ 𝐸))) | 
| 26 | 15, 19, 25 | 3bitr4i 303 | 1
⊢ (𝑊 ∈ (ClWWalks‘𝐺) ↔ ((𝑊 ∈ Word 𝑉 ∧ 𝑊 ≠ ∅) ∧ ∀𝑖 ∈
(0..^((♯‘𝑊)
− 1)){(𝑊‘𝑖), (𝑊‘(𝑖 + 1))} ∈ 𝐸 ∧ {(lastS‘𝑊), (𝑊‘0)} ∈ 𝐸)) |