| Step | Hyp | Ref | Expression | 
|---|
| 1 |  | ovex 7464 | . . . . 5
⊢ (𝑁 WWalksN 𝐺) ∈ V | 
| 2 | 1 | mptrabex 7245 | . . . 4
⊢ (𝑤 ∈ {𝑥 ∈ (𝑁 WWalksN 𝐺) ∣ (lastS‘𝑥) = (𝑥‘0)} ↦ (𝑤 prefix 𝑁)) ∈ V | 
| 3 | 2 | resex 6047 | . . 3
⊢ ((𝑤 ∈ {𝑥 ∈ (𝑁 WWalksN 𝐺) ∣ (lastS‘𝑥) = (𝑥‘0)} ↦ (𝑤 prefix 𝑁)) ↾ {𝑤 ∈ {𝑥 ∈ (𝑁 WWalksN 𝐺) ∣ (lastS‘𝑥) = (𝑥‘0)} ∣ (𝑤‘0) = 𝑋}) ∈ V | 
| 4 |  | eqid 2737 | . . . . . 6
⊢ (𝑤 ∈ {𝑥 ∈ (𝑁 WWalksN 𝐺) ∣ (lastS‘𝑥) = (𝑥‘0)} ↦ (𝑤 prefix 𝑁)) = (𝑤 ∈ {𝑥 ∈ (𝑁 WWalksN 𝐺) ∣ (lastS‘𝑥) = (𝑥‘0)} ↦ (𝑤 prefix 𝑁)) | 
| 5 |  | eqid 2737 | . . . . . . 7
⊢ {𝑥 ∈ (𝑁 WWalksN 𝐺) ∣ (lastS‘𝑥) = (𝑥‘0)} = {𝑥 ∈ (𝑁 WWalksN 𝐺) ∣ (lastS‘𝑥) = (𝑥‘0)} | 
| 6 | 5, 4 | clwwlkf1o 30070 | . . . . . 6
⊢ (𝑁 ∈ ℕ → (𝑤 ∈ {𝑥 ∈ (𝑁 WWalksN 𝐺) ∣ (lastS‘𝑥) = (𝑥‘0)} ↦ (𝑤 prefix 𝑁)):{𝑥 ∈ (𝑁 WWalksN 𝐺) ∣ (lastS‘𝑥) = (𝑥‘0)}–1-1-onto→(𝑁 ClWWalksN 𝐺)) | 
| 7 |  | fveq1 6905 | . . . . . . . . 9
⊢ (𝑦 = (𝑤 prefix 𝑁) → (𝑦‘0) = ((𝑤 prefix 𝑁)‘0)) | 
| 8 | 7 | eqeq1d 2739 | . . . . . . . 8
⊢ (𝑦 = (𝑤 prefix 𝑁) → ((𝑦‘0) = 𝑋 ↔ ((𝑤 prefix 𝑁)‘0) = 𝑋)) | 
| 9 | 8 | 3ad2ant3 1136 | . . . . . . 7
⊢ ((𝑁 ∈ ℕ ∧ 𝑤 ∈ {𝑥 ∈ (𝑁 WWalksN 𝐺) ∣ (lastS‘𝑥) = (𝑥‘0)} ∧ 𝑦 = (𝑤 prefix 𝑁)) → ((𝑦‘0) = 𝑋 ↔ ((𝑤 prefix 𝑁)‘0) = 𝑋)) | 
| 10 |  | fveq2 6906 | . . . . . . . . . . . . . 14
⊢ (𝑥 = 𝑤 → (lastS‘𝑥) = (lastS‘𝑤)) | 
| 11 |  | fveq1 6905 | . . . . . . . . . . . . . 14
⊢ (𝑥 = 𝑤 → (𝑥‘0) = (𝑤‘0)) | 
| 12 | 10, 11 | eqeq12d 2753 | . . . . . . . . . . . . 13
⊢ (𝑥 = 𝑤 → ((lastS‘𝑥) = (𝑥‘0) ↔ (lastS‘𝑤) = (𝑤‘0))) | 
| 13 | 12 | elrab 3692 | . . . . . . . . . . . 12
⊢ (𝑤 ∈ {𝑥 ∈ (𝑁 WWalksN 𝐺) ∣ (lastS‘𝑥) = (𝑥‘0)} ↔ (𝑤 ∈ (𝑁 WWalksN 𝐺) ∧ (lastS‘𝑤) = (𝑤‘0))) | 
| 14 |  | eqid 2737 | . . . . . . . . . . . . . . 15
⊢
(Vtx‘𝐺) =
(Vtx‘𝐺) | 
| 15 |  | eqid 2737 | . . . . . . . . . . . . . . 15
⊢
(Edg‘𝐺) =
(Edg‘𝐺) | 
| 16 | 14, 15 | wwlknp 29863 | . . . . . . . . . . . . . 14
⊢ (𝑤 ∈ (𝑁 WWalksN 𝐺) → (𝑤 ∈ Word (Vtx‘𝐺) ∧ (♯‘𝑤) = (𝑁 + 1) ∧ ∀𝑖 ∈ (0..^𝑁){(𝑤‘𝑖), (𝑤‘(𝑖 + 1))} ∈ (Edg‘𝐺))) | 
| 17 |  | simpll 767 | . . . . . . . . . . . . . . . . 17
⊢ (((𝑤 ∈ Word (Vtx‘𝐺) ∧ (♯‘𝑤) = (𝑁 + 1)) ∧ 𝑁 ∈ ℕ) → 𝑤 ∈ Word (Vtx‘𝐺)) | 
| 18 |  | nnz 12634 | . . . . . . . . . . . . . . . . . . . . 21
⊢ (𝑁 ∈ ℕ → 𝑁 ∈
ℤ) | 
| 19 |  | uzid 12893 | . . . . . . . . . . . . . . . . . . . . 21
⊢ (𝑁 ∈ ℤ → 𝑁 ∈
(ℤ≥‘𝑁)) | 
| 20 |  | peano2uz 12943 | . . . . . . . . . . . . . . . . . . . . 21
⊢ (𝑁 ∈
(ℤ≥‘𝑁) → (𝑁 + 1) ∈
(ℤ≥‘𝑁)) | 
| 21 | 18, 19, 20 | 3syl 18 | . . . . . . . . . . . . . . . . . . . 20
⊢ (𝑁 ∈ ℕ → (𝑁 + 1) ∈
(ℤ≥‘𝑁)) | 
| 22 |  | elfz1end 13594 | . . . . . . . . . . . . . . . . . . . . 21
⊢ (𝑁 ∈ ℕ ↔ 𝑁 ∈ (1...𝑁)) | 
| 23 | 22 | biimpi 216 | . . . . . . . . . . . . . . . . . . . 20
⊢ (𝑁 ∈ ℕ → 𝑁 ∈ (1...𝑁)) | 
| 24 |  | fzss2 13604 | . . . . . . . . . . . . . . . . . . . . 21
⊢ ((𝑁 + 1) ∈
(ℤ≥‘𝑁) → (1...𝑁) ⊆ (1...(𝑁 + 1))) | 
| 25 | 24 | sselda 3983 | . . . . . . . . . . . . . . . . . . . 20
⊢ (((𝑁 + 1) ∈
(ℤ≥‘𝑁) ∧ 𝑁 ∈ (1...𝑁)) → 𝑁 ∈ (1...(𝑁 + 1))) | 
| 26 | 21, 23, 25 | syl2anc 584 | . . . . . . . . . . . . . . . . . . 19
⊢ (𝑁 ∈ ℕ → 𝑁 ∈ (1...(𝑁 + 1))) | 
| 27 | 26 | adantl 481 | . . . . . . . . . . . . . . . . . 18
⊢ (((𝑤 ∈ Word (Vtx‘𝐺) ∧ (♯‘𝑤) = (𝑁 + 1)) ∧ 𝑁 ∈ ℕ) → 𝑁 ∈ (1...(𝑁 + 1))) | 
| 28 |  | oveq2 7439 | . . . . . . . . . . . . . . . . . . . . 21
⊢
((♯‘𝑤) =
(𝑁 + 1) →
(1...(♯‘𝑤)) =
(1...(𝑁 +
1))) | 
| 29 | 28 | eleq2d 2827 | . . . . . . . . . . . . . . . . . . . 20
⊢
((♯‘𝑤) =
(𝑁 + 1) → (𝑁 ∈
(1...(♯‘𝑤))
↔ 𝑁 ∈ (1...(𝑁 + 1)))) | 
| 30 | 29 | adantl 481 | . . . . . . . . . . . . . . . . . . 19
⊢ ((𝑤 ∈ Word (Vtx‘𝐺) ∧ (♯‘𝑤) = (𝑁 + 1)) → (𝑁 ∈ (1...(♯‘𝑤)) ↔ 𝑁 ∈ (1...(𝑁 + 1)))) | 
| 31 | 30 | adantr 480 | . . . . . . . . . . . . . . . . . 18
⊢ (((𝑤 ∈ Word (Vtx‘𝐺) ∧ (♯‘𝑤) = (𝑁 + 1)) ∧ 𝑁 ∈ ℕ) → (𝑁 ∈ (1...(♯‘𝑤)) ↔ 𝑁 ∈ (1...(𝑁 + 1)))) | 
| 32 | 27, 31 | mpbird 257 | . . . . . . . . . . . . . . . . 17
⊢ (((𝑤 ∈ Word (Vtx‘𝐺) ∧ (♯‘𝑤) = (𝑁 + 1)) ∧ 𝑁 ∈ ℕ) → 𝑁 ∈ (1...(♯‘𝑤))) | 
| 33 | 17, 32 | jca 511 | . . . . . . . . . . . . . . . 16
⊢ (((𝑤 ∈ Word (Vtx‘𝐺) ∧ (♯‘𝑤) = (𝑁 + 1)) ∧ 𝑁 ∈ ℕ) → (𝑤 ∈ Word (Vtx‘𝐺) ∧ 𝑁 ∈ (1...(♯‘𝑤)))) | 
| 34 | 33 | ex 412 | . . . . . . . . . . . . . . 15
⊢ ((𝑤 ∈ Word (Vtx‘𝐺) ∧ (♯‘𝑤) = (𝑁 + 1)) → (𝑁 ∈ ℕ → (𝑤 ∈ Word (Vtx‘𝐺) ∧ 𝑁 ∈ (1...(♯‘𝑤))))) | 
| 35 | 34 | 3adant3 1133 | . . . . . . . . . . . . . 14
⊢ ((𝑤 ∈ Word (Vtx‘𝐺) ∧ (♯‘𝑤) = (𝑁 + 1) ∧ ∀𝑖 ∈ (0..^𝑁){(𝑤‘𝑖), (𝑤‘(𝑖 + 1))} ∈ (Edg‘𝐺)) → (𝑁 ∈ ℕ → (𝑤 ∈ Word (Vtx‘𝐺) ∧ 𝑁 ∈ (1...(♯‘𝑤))))) | 
| 36 | 16, 35 | syl 17 | . . . . . . . . . . . . 13
⊢ (𝑤 ∈ (𝑁 WWalksN 𝐺) → (𝑁 ∈ ℕ → (𝑤 ∈ Word (Vtx‘𝐺) ∧ 𝑁 ∈ (1...(♯‘𝑤))))) | 
| 37 | 36 | adantr 480 | . . . . . . . . . . . 12
⊢ ((𝑤 ∈ (𝑁 WWalksN 𝐺) ∧ (lastS‘𝑤) = (𝑤‘0)) → (𝑁 ∈ ℕ → (𝑤 ∈ Word (Vtx‘𝐺) ∧ 𝑁 ∈ (1...(♯‘𝑤))))) | 
| 38 | 13, 37 | sylbi 217 | . . . . . . . . . . 11
⊢ (𝑤 ∈ {𝑥 ∈ (𝑁 WWalksN 𝐺) ∣ (lastS‘𝑥) = (𝑥‘0)} → (𝑁 ∈ ℕ → (𝑤 ∈ Word (Vtx‘𝐺) ∧ 𝑁 ∈ (1...(♯‘𝑤))))) | 
| 39 | 38 | impcom 407 | . . . . . . . . . 10
⊢ ((𝑁 ∈ ℕ ∧ 𝑤 ∈ {𝑥 ∈ (𝑁 WWalksN 𝐺) ∣ (lastS‘𝑥) = (𝑥‘0)}) → (𝑤 ∈ Word (Vtx‘𝐺) ∧ 𝑁 ∈ (1...(♯‘𝑤)))) | 
| 40 |  | pfxfv0 14730 | . . . . . . . . . 10
⊢ ((𝑤 ∈ Word (Vtx‘𝐺) ∧ 𝑁 ∈ (1...(♯‘𝑤))) → ((𝑤 prefix 𝑁)‘0) = (𝑤‘0)) | 
| 41 | 39, 40 | syl 17 | . . . . . . . . 9
⊢ ((𝑁 ∈ ℕ ∧ 𝑤 ∈ {𝑥 ∈ (𝑁 WWalksN 𝐺) ∣ (lastS‘𝑥) = (𝑥‘0)}) → ((𝑤 prefix 𝑁)‘0) = (𝑤‘0)) | 
| 42 | 41 | eqeq1d 2739 | . . . . . . . 8
⊢ ((𝑁 ∈ ℕ ∧ 𝑤 ∈ {𝑥 ∈ (𝑁 WWalksN 𝐺) ∣ (lastS‘𝑥) = (𝑥‘0)}) → (((𝑤 prefix 𝑁)‘0) = 𝑋 ↔ (𝑤‘0) = 𝑋)) | 
| 43 | 42 | 3adant3 1133 | . . . . . . 7
⊢ ((𝑁 ∈ ℕ ∧ 𝑤 ∈ {𝑥 ∈ (𝑁 WWalksN 𝐺) ∣ (lastS‘𝑥) = (𝑥‘0)} ∧ 𝑦 = (𝑤 prefix 𝑁)) → (((𝑤 prefix 𝑁)‘0) = 𝑋 ↔ (𝑤‘0) = 𝑋)) | 
| 44 | 9, 43 | bitrd 279 | . . . . . 6
⊢ ((𝑁 ∈ ℕ ∧ 𝑤 ∈ {𝑥 ∈ (𝑁 WWalksN 𝐺) ∣ (lastS‘𝑥) = (𝑥‘0)} ∧ 𝑦 = (𝑤 prefix 𝑁)) → ((𝑦‘0) = 𝑋 ↔ (𝑤‘0) = 𝑋)) | 
| 45 | 4, 6, 44 | f1oresrab 7147 | . . . . 5
⊢ (𝑁 ∈ ℕ → ((𝑤 ∈ {𝑥 ∈ (𝑁 WWalksN 𝐺) ∣ (lastS‘𝑥) = (𝑥‘0)} ↦ (𝑤 prefix 𝑁)) ↾ {𝑤 ∈ {𝑥 ∈ (𝑁 WWalksN 𝐺) ∣ (lastS‘𝑥) = (𝑥‘0)} ∣ (𝑤‘0) = 𝑋}):{𝑤 ∈ {𝑥 ∈ (𝑁 WWalksN 𝐺) ∣ (lastS‘𝑥) = (𝑥‘0)} ∣ (𝑤‘0) = 𝑋}–1-1-onto→{𝑦 ∈ (𝑁 ClWWalksN 𝐺) ∣ (𝑦‘0) = 𝑋}) | 
| 46 | 45 | adantl 481 | . . . 4
⊢ ((𝑋 ∈ 𝑉 ∧ 𝑁 ∈ ℕ) → ((𝑤 ∈ {𝑥 ∈ (𝑁 WWalksN 𝐺) ∣ (lastS‘𝑥) = (𝑥‘0)} ↦ (𝑤 prefix 𝑁)) ↾ {𝑤 ∈ {𝑥 ∈ (𝑁 WWalksN 𝐺) ∣ (lastS‘𝑥) = (𝑥‘0)} ∣ (𝑤‘0) = 𝑋}):{𝑤 ∈ {𝑥 ∈ (𝑁 WWalksN 𝐺) ∣ (lastS‘𝑥) = (𝑥‘0)} ∣ (𝑤‘0) = 𝑋}–1-1-onto→{𝑦 ∈ (𝑁 ClWWalksN 𝐺) ∣ (𝑦‘0) = 𝑋}) | 
| 47 |  | clwwlknon 30109 | . . . . . 6
⊢ (𝑋(ClWWalksNOn‘𝐺)𝑁) = {𝑦 ∈ (𝑁 ClWWalksN 𝐺) ∣ (𝑦‘0) = 𝑋} | 
| 48 | 47 | a1i 11 | . . . . 5
⊢ ((𝑋 ∈ 𝑉 ∧ 𝑁 ∈ ℕ) → (𝑋(ClWWalksNOn‘𝐺)𝑁) = {𝑦 ∈ (𝑁 ClWWalksN 𝐺) ∣ (𝑦‘0) = 𝑋}) | 
| 49 | 48 | f1oeq3d 6845 | . . . 4
⊢ ((𝑋 ∈ 𝑉 ∧ 𝑁 ∈ ℕ) → (((𝑤 ∈ {𝑥 ∈ (𝑁 WWalksN 𝐺) ∣ (lastS‘𝑥) = (𝑥‘0)} ↦ (𝑤 prefix 𝑁)) ↾ {𝑤 ∈ {𝑥 ∈ (𝑁 WWalksN 𝐺) ∣ (lastS‘𝑥) = (𝑥‘0)} ∣ (𝑤‘0) = 𝑋}):{𝑤 ∈ {𝑥 ∈ (𝑁 WWalksN 𝐺) ∣ (lastS‘𝑥) = (𝑥‘0)} ∣ (𝑤‘0) = 𝑋}–1-1-onto→(𝑋(ClWWalksNOn‘𝐺)𝑁) ↔ ((𝑤 ∈ {𝑥 ∈ (𝑁 WWalksN 𝐺) ∣ (lastS‘𝑥) = (𝑥‘0)} ↦ (𝑤 prefix 𝑁)) ↾ {𝑤 ∈ {𝑥 ∈ (𝑁 WWalksN 𝐺) ∣ (lastS‘𝑥) = (𝑥‘0)} ∣ (𝑤‘0) = 𝑋}):{𝑤 ∈ {𝑥 ∈ (𝑁 WWalksN 𝐺) ∣ (lastS‘𝑥) = (𝑥‘0)} ∣ (𝑤‘0) = 𝑋}–1-1-onto→{𝑦 ∈ (𝑁 ClWWalksN 𝐺) ∣ (𝑦‘0) = 𝑋})) | 
| 50 | 46, 49 | mpbird 257 | . . 3
⊢ ((𝑋 ∈ 𝑉 ∧ 𝑁 ∈ ℕ) → ((𝑤 ∈ {𝑥 ∈ (𝑁 WWalksN 𝐺) ∣ (lastS‘𝑥) = (𝑥‘0)} ↦ (𝑤 prefix 𝑁)) ↾ {𝑤 ∈ {𝑥 ∈ (𝑁 WWalksN 𝐺) ∣ (lastS‘𝑥) = (𝑥‘0)} ∣ (𝑤‘0) = 𝑋}):{𝑤 ∈ {𝑥 ∈ (𝑁 WWalksN 𝐺) ∣ (lastS‘𝑥) = (𝑥‘0)} ∣ (𝑤‘0) = 𝑋}–1-1-onto→(𝑋(ClWWalksNOn‘𝐺)𝑁)) | 
| 51 |  | f1oeq1 6836 | . . . 4
⊢ (𝑓 = ((𝑤 ∈ {𝑥 ∈ (𝑁 WWalksN 𝐺) ∣ (lastS‘𝑥) = (𝑥‘0)} ↦ (𝑤 prefix 𝑁)) ↾ {𝑤 ∈ {𝑥 ∈ (𝑁 WWalksN 𝐺) ∣ (lastS‘𝑥) = (𝑥‘0)} ∣ (𝑤‘0) = 𝑋}) → (𝑓:{𝑤 ∈ {𝑥 ∈ (𝑁 WWalksN 𝐺) ∣ (lastS‘𝑥) = (𝑥‘0)} ∣ (𝑤‘0) = 𝑋}–1-1-onto→(𝑋(ClWWalksNOn‘𝐺)𝑁) ↔ ((𝑤 ∈ {𝑥 ∈ (𝑁 WWalksN 𝐺) ∣ (lastS‘𝑥) = (𝑥‘0)} ↦ (𝑤 prefix 𝑁)) ↾ {𝑤 ∈ {𝑥 ∈ (𝑁 WWalksN 𝐺) ∣ (lastS‘𝑥) = (𝑥‘0)} ∣ (𝑤‘0) = 𝑋}):{𝑤 ∈ {𝑥 ∈ (𝑁 WWalksN 𝐺) ∣ (lastS‘𝑥) = (𝑥‘0)} ∣ (𝑤‘0) = 𝑋}–1-1-onto→(𝑋(ClWWalksNOn‘𝐺)𝑁))) | 
| 52 | 51 | spcegv 3597 | . . 3
⊢ (((𝑤 ∈ {𝑥 ∈ (𝑁 WWalksN 𝐺) ∣ (lastS‘𝑥) = (𝑥‘0)} ↦ (𝑤 prefix 𝑁)) ↾ {𝑤 ∈ {𝑥 ∈ (𝑁 WWalksN 𝐺) ∣ (lastS‘𝑥) = (𝑥‘0)} ∣ (𝑤‘0) = 𝑋}) ∈ V → (((𝑤 ∈ {𝑥 ∈ (𝑁 WWalksN 𝐺) ∣ (lastS‘𝑥) = (𝑥‘0)} ↦ (𝑤 prefix 𝑁)) ↾ {𝑤 ∈ {𝑥 ∈ (𝑁 WWalksN 𝐺) ∣ (lastS‘𝑥) = (𝑥‘0)} ∣ (𝑤‘0) = 𝑋}):{𝑤 ∈ {𝑥 ∈ (𝑁 WWalksN 𝐺) ∣ (lastS‘𝑥) = (𝑥‘0)} ∣ (𝑤‘0) = 𝑋}–1-1-onto→(𝑋(ClWWalksNOn‘𝐺)𝑁) → ∃𝑓 𝑓:{𝑤 ∈ {𝑥 ∈ (𝑁 WWalksN 𝐺) ∣ (lastS‘𝑥) = (𝑥‘0)} ∣ (𝑤‘0) = 𝑋}–1-1-onto→(𝑋(ClWWalksNOn‘𝐺)𝑁))) | 
| 53 | 3, 50, 52 | mpsyl 68 | . 2
⊢ ((𝑋 ∈ 𝑉 ∧ 𝑁 ∈ ℕ) → ∃𝑓 𝑓:{𝑤 ∈ {𝑥 ∈ (𝑁 WWalksN 𝐺) ∣ (lastS‘𝑥) = (𝑥‘0)} ∣ (𝑤‘0) = 𝑋}–1-1-onto→(𝑋(ClWWalksNOn‘𝐺)𝑁)) | 
| 54 |  | df-rab 3437 | . . . . 5
⊢ {𝑤 ∈ (𝑁 WWalksN 𝐺) ∣ ((lastS‘𝑤) = (𝑤‘0) ∧ (𝑤‘0) = 𝑋)} = {𝑤 ∣ (𝑤 ∈ (𝑁 WWalksN 𝐺) ∧ ((lastS‘𝑤) = (𝑤‘0) ∧ (𝑤‘0) = 𝑋))} | 
| 55 |  | anass 468 | . . . . . . 7
⊢ (((𝑤 ∈ (𝑁 WWalksN 𝐺) ∧ (lastS‘𝑤) = (𝑤‘0)) ∧ (𝑤‘0) = 𝑋) ↔ (𝑤 ∈ (𝑁 WWalksN 𝐺) ∧ ((lastS‘𝑤) = (𝑤‘0) ∧ (𝑤‘0) = 𝑋))) | 
| 56 | 55 | bicomi 224 | . . . . . 6
⊢ ((𝑤 ∈ (𝑁 WWalksN 𝐺) ∧ ((lastS‘𝑤) = (𝑤‘0) ∧ (𝑤‘0) = 𝑋)) ↔ ((𝑤 ∈ (𝑁 WWalksN 𝐺) ∧ (lastS‘𝑤) = (𝑤‘0)) ∧ (𝑤‘0) = 𝑋)) | 
| 57 | 56 | abbii 2809 | . . . . 5
⊢ {𝑤 ∣ (𝑤 ∈ (𝑁 WWalksN 𝐺) ∧ ((lastS‘𝑤) = (𝑤‘0) ∧ (𝑤‘0) = 𝑋))} = {𝑤 ∣ ((𝑤 ∈ (𝑁 WWalksN 𝐺) ∧ (lastS‘𝑤) = (𝑤‘0)) ∧ (𝑤‘0) = 𝑋)} | 
| 58 | 13 | bicomi 224 | . . . . . . . 8
⊢ ((𝑤 ∈ (𝑁 WWalksN 𝐺) ∧ (lastS‘𝑤) = (𝑤‘0)) ↔ 𝑤 ∈ {𝑥 ∈ (𝑁 WWalksN 𝐺) ∣ (lastS‘𝑥) = (𝑥‘0)}) | 
| 59 | 58 | anbi1i 624 | . . . . . . 7
⊢ (((𝑤 ∈ (𝑁 WWalksN 𝐺) ∧ (lastS‘𝑤) = (𝑤‘0)) ∧ (𝑤‘0) = 𝑋) ↔ (𝑤 ∈ {𝑥 ∈ (𝑁 WWalksN 𝐺) ∣ (lastS‘𝑥) = (𝑥‘0)} ∧ (𝑤‘0) = 𝑋)) | 
| 60 | 59 | abbii 2809 | . . . . . 6
⊢ {𝑤 ∣ ((𝑤 ∈ (𝑁 WWalksN 𝐺) ∧ (lastS‘𝑤) = (𝑤‘0)) ∧ (𝑤‘0) = 𝑋)} = {𝑤 ∣ (𝑤 ∈ {𝑥 ∈ (𝑁 WWalksN 𝐺) ∣ (lastS‘𝑥) = (𝑥‘0)} ∧ (𝑤‘0) = 𝑋)} | 
| 61 |  | df-rab 3437 | . . . . . 6
⊢ {𝑤 ∈ {𝑥 ∈ (𝑁 WWalksN 𝐺) ∣ (lastS‘𝑥) = (𝑥‘0)} ∣ (𝑤‘0) = 𝑋} = {𝑤 ∣ (𝑤 ∈ {𝑥 ∈ (𝑁 WWalksN 𝐺) ∣ (lastS‘𝑥) = (𝑥‘0)} ∧ (𝑤‘0) = 𝑋)} | 
| 62 | 60, 61 | eqtr4i 2768 | . . . . 5
⊢ {𝑤 ∣ ((𝑤 ∈ (𝑁 WWalksN 𝐺) ∧ (lastS‘𝑤) = (𝑤‘0)) ∧ (𝑤‘0) = 𝑋)} = {𝑤 ∈ {𝑥 ∈ (𝑁 WWalksN 𝐺) ∣ (lastS‘𝑥) = (𝑥‘0)} ∣ (𝑤‘0) = 𝑋} | 
| 63 | 54, 57, 62 | 3eqtri 2769 | . . . 4
⊢ {𝑤 ∈ (𝑁 WWalksN 𝐺) ∣ ((lastS‘𝑤) = (𝑤‘0) ∧ (𝑤‘0) = 𝑋)} = {𝑤 ∈ {𝑥 ∈ (𝑁 WWalksN 𝐺) ∣ (lastS‘𝑥) = (𝑥‘0)} ∣ (𝑤‘0) = 𝑋} | 
| 64 |  | f1oeq2 6837 | . . . 4
⊢ ({𝑤 ∈ (𝑁 WWalksN 𝐺) ∣ ((lastS‘𝑤) = (𝑤‘0) ∧ (𝑤‘0) = 𝑋)} = {𝑤 ∈ {𝑥 ∈ (𝑁 WWalksN 𝐺) ∣ (lastS‘𝑥) = (𝑥‘0)} ∣ (𝑤‘0) = 𝑋} → (𝑓:{𝑤 ∈ (𝑁 WWalksN 𝐺) ∣ ((lastS‘𝑤) = (𝑤‘0) ∧ (𝑤‘0) = 𝑋)}–1-1-onto→(𝑋(ClWWalksNOn‘𝐺)𝑁) ↔ 𝑓:{𝑤 ∈ {𝑥 ∈ (𝑁 WWalksN 𝐺) ∣ (lastS‘𝑥) = (𝑥‘0)} ∣ (𝑤‘0) = 𝑋}–1-1-onto→(𝑋(ClWWalksNOn‘𝐺)𝑁))) | 
| 65 | 63, 64 | mp1i 13 | . . 3
⊢ ((𝑋 ∈ 𝑉 ∧ 𝑁 ∈ ℕ) → (𝑓:{𝑤 ∈ (𝑁 WWalksN 𝐺) ∣ ((lastS‘𝑤) = (𝑤‘0) ∧ (𝑤‘0) = 𝑋)}–1-1-onto→(𝑋(ClWWalksNOn‘𝐺)𝑁) ↔ 𝑓:{𝑤 ∈ {𝑥 ∈ (𝑁 WWalksN 𝐺) ∣ (lastS‘𝑥) = (𝑥‘0)} ∣ (𝑤‘0) = 𝑋}–1-1-onto→(𝑋(ClWWalksNOn‘𝐺)𝑁))) | 
| 66 | 65 | exbidv 1921 | . 2
⊢ ((𝑋 ∈ 𝑉 ∧ 𝑁 ∈ ℕ) → (∃𝑓 𝑓:{𝑤 ∈ (𝑁 WWalksN 𝐺) ∣ ((lastS‘𝑤) = (𝑤‘0) ∧ (𝑤‘0) = 𝑋)}–1-1-onto→(𝑋(ClWWalksNOn‘𝐺)𝑁) ↔ ∃𝑓 𝑓:{𝑤 ∈ {𝑥 ∈ (𝑁 WWalksN 𝐺) ∣ (lastS‘𝑥) = (𝑥‘0)} ∣ (𝑤‘0) = 𝑋}–1-1-onto→(𝑋(ClWWalksNOn‘𝐺)𝑁))) | 
| 67 | 53, 66 | mpbird 257 | 1
⊢ ((𝑋 ∈ 𝑉 ∧ 𝑁 ∈ ℕ) → ∃𝑓 𝑓:{𝑤 ∈ (𝑁 WWalksN 𝐺) ∣ ((lastS‘𝑤) = (𝑤‘0) ∧ (𝑤‘0) = 𝑋)}–1-1-onto→(𝑋(ClWWalksNOn‘𝐺)𝑁)) |