Proof of Theorem usgr2pthlem
| Step | Hyp | Ref | Expression | 
|---|
| 1 |  | 0nn0 12543 | . . . . . . . . . . . . . 14
⊢ 0 ∈
ℕ0 | 
| 2 |  | 2nn0 12545 | . . . . . . . . . . . . . 14
⊢ 2 ∈
ℕ0 | 
| 3 |  | 0le2 12369 | . . . . . . . . . . . . . 14
⊢ 0 ≤
2 | 
| 4 |  | elfz2nn0 13659 | . . . . . . . . . . . . . 14
⊢ (0 ∈
(0...2) ↔ (0 ∈ ℕ0 ∧ 2 ∈ ℕ0
∧ 0 ≤ 2)) | 
| 5 | 1, 2, 3, 4 | mpbir3an 1341 | . . . . . . . . . . . . 13
⊢ 0 ∈
(0...2) | 
| 6 |  | ffvelcdm 7100 | . . . . . . . . . . . . 13
⊢ ((𝑃:(0...2)⟶𝑉 ∧ 0 ∈ (0...2)) →
(𝑃‘0) ∈ 𝑉) | 
| 7 | 5, 6 | mpan2 691 | . . . . . . . . . . . 12
⊢ (𝑃:(0...2)⟶𝑉 → (𝑃‘0) ∈ 𝑉) | 
| 8 | 7 | adantl 481 | . . . . . . . . . . 11
⊢ ((((𝐹:(0..^2)–1-1→dom 𝐼 ∧ ((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)})) ∧ 𝐺 ∈ USGraph) ∧ 𝑃:(0...2)⟶𝑉) → (𝑃‘0) ∈ 𝑉) | 
| 9 |  | 1nn0 12544 | . . . . . . . . . . . . . . . . . 18
⊢ 1 ∈
ℕ0 | 
| 10 |  | 1le2 12476 | . . . . . . . . . . . . . . . . . 18
⊢ 1 ≤
2 | 
| 11 |  | elfz2nn0 13659 | . . . . . . . . . . . . . . . . . 18
⊢ (1 ∈
(0...2) ↔ (1 ∈ ℕ0 ∧ 2 ∈ ℕ0
∧ 1 ≤ 2)) | 
| 12 | 9, 2, 10, 11 | mpbir3an 1341 | . . . . . . . . . . . . . . . . 17
⊢ 1 ∈
(0...2) | 
| 13 |  | ffvelcdm 7100 | . . . . . . . . . . . . . . . . 17
⊢ ((𝑃:(0...2)⟶𝑉 ∧ 1 ∈ (0...2)) →
(𝑃‘1) ∈ 𝑉) | 
| 14 | 12, 13 | mpan2 691 | . . . . . . . . . . . . . . . 16
⊢ (𝑃:(0...2)⟶𝑉 → (𝑃‘1) ∈ 𝑉) | 
| 15 | 14 | adantl 481 | . . . . . . . . . . . . . . 15
⊢ ((((𝐹:(0..^2)–1-1→dom 𝐼 ∧ ((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)})) ∧ 𝐺 ∈ USGraph) ∧ 𝑃:(0...2)⟶𝑉) → (𝑃‘1) ∈ 𝑉) | 
| 16 |  | simpr 484 | . . . . . . . . . . . . . . . . . . 19
⊢ (((𝐹:(0..^2)–1-1→dom 𝐼 ∧ ((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)})) ∧ 𝐺 ∈ USGraph) → 𝐺 ∈ USGraph) | 
| 17 |  | fvex 6918 | . . . . . . . . . . . . . . . . . . 19
⊢ (𝑃‘1) ∈
V | 
| 18 | 16, 17 | jctir 520 | . . . . . . . . . . . . . . . . . 18
⊢ (((𝐹:(0..^2)–1-1→dom 𝐼 ∧ ((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)})) ∧ 𝐺 ∈ USGraph) → (𝐺 ∈ USGraph ∧ (𝑃‘1) ∈ V)) | 
| 19 |  | prcom 4731 | . . . . . . . . . . . . . . . . . . . . . 22
⊢ {(𝑃‘0), (𝑃‘1)} = {(𝑃‘1), (𝑃‘0)} | 
| 20 | 19 | eqeq2i 2749 | . . . . . . . . . . . . . . . . . . . . 21
⊢ ((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ↔ (𝐼‘(𝐹‘0)) = {(𝑃‘1), (𝑃‘0)}) | 
| 21 | 20 | biimpi 216 | . . . . . . . . . . . . . . . . . . . 20
⊢ ((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} → (𝐼‘(𝐹‘0)) = {(𝑃‘1), (𝑃‘0)}) | 
| 22 | 21 | adantr 480 | . . . . . . . . . . . . . . . . . . 19
⊢ (((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)}) → (𝐼‘(𝐹‘0)) = {(𝑃‘1), (𝑃‘0)}) | 
| 23 | 22 | ad2antlr 727 | . . . . . . . . . . . . . . . . . 18
⊢ (((𝐹:(0..^2)–1-1→dom 𝐼 ∧ ((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)})) ∧ 𝐺 ∈ USGraph) → (𝐼‘(𝐹‘0)) = {(𝑃‘1), (𝑃‘0)}) | 
| 24 |  | usgr2pthlem.i | . . . . . . . . . . . . . . . . . . 19
⊢ 𝐼 = (iEdg‘𝐺) | 
| 25 | 24 | usgrnloopv 29218 | . . . . . . . . . . . . . . . . . 18
⊢ ((𝐺 ∈ USGraph ∧ (𝑃‘1) ∈ V) →
((𝐼‘(𝐹‘0)) = {(𝑃‘1), (𝑃‘0)} → (𝑃‘1) ≠ (𝑃‘0))) | 
| 26 | 18, 23, 25 | sylc 65 | . . . . . . . . . . . . . . . . 17
⊢ (((𝐹:(0..^2)–1-1→dom 𝐼 ∧ ((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)})) ∧ 𝐺 ∈ USGraph) → (𝑃‘1) ≠ (𝑃‘0)) | 
| 27 | 26 | adantr 480 | . . . . . . . . . . . . . . . 16
⊢ ((((𝐹:(0..^2)–1-1→dom 𝐼 ∧ ((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)})) ∧ 𝐺 ∈ USGraph) ∧ 𝑃:(0...2)⟶𝑉) → (𝑃‘1) ≠ (𝑃‘0)) | 
| 28 | 17 | elsn 4640 | . . . . . . . . . . . . . . . . 17
⊢ ((𝑃‘1) ∈ {(𝑃‘0)} ↔ (𝑃‘1) = (𝑃‘0)) | 
| 29 | 28 | necon3bbii 2987 | . . . . . . . . . . . . . . . 16
⊢ (¬
(𝑃‘1) ∈ {(𝑃‘0)} ↔ (𝑃‘1) ≠ (𝑃‘0)) | 
| 30 | 27, 29 | sylibr 234 | . . . . . . . . . . . . . . 15
⊢ ((((𝐹:(0..^2)–1-1→dom 𝐼 ∧ ((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)})) ∧ 𝐺 ∈ USGraph) ∧ 𝑃:(0...2)⟶𝑉) → ¬ (𝑃‘1) ∈ {(𝑃‘0)}) | 
| 31 | 15, 30 | eldifd 3961 | . . . . . . . . . . . . . 14
⊢ ((((𝐹:(0..^2)–1-1→dom 𝐼 ∧ ((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)})) ∧ 𝐺 ∈ USGraph) ∧ 𝑃:(0...2)⟶𝑉) → (𝑃‘1) ∈ (𝑉 ∖ {(𝑃‘0)})) | 
| 32 | 31 | adantr 480 | . . . . . . . . . . . . 13
⊢
(((((𝐹:(0..^2)–1-1→dom 𝐼 ∧ ((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)})) ∧ 𝐺 ∈ USGraph) ∧ 𝑃:(0...2)⟶𝑉) ∧ 𝑥 = (𝑃‘0)) → (𝑃‘1) ∈ (𝑉 ∖ {(𝑃‘0)})) | 
| 33 |  | sneq 4635 | . . . . . . . . . . . . . . . 16
⊢ (𝑥 = (𝑃‘0) → {𝑥} = {(𝑃‘0)}) | 
| 34 | 33 | difeq2d 4125 | . . . . . . . . . . . . . . 15
⊢ (𝑥 = (𝑃‘0) → (𝑉 ∖ {𝑥}) = (𝑉 ∖ {(𝑃‘0)})) | 
| 35 | 34 | eleq2d 2826 | . . . . . . . . . . . . . 14
⊢ (𝑥 = (𝑃‘0) → ((𝑃‘1) ∈ (𝑉 ∖ {𝑥}) ↔ (𝑃‘1) ∈ (𝑉 ∖ {(𝑃‘0)}))) | 
| 36 | 35 | adantl 481 | . . . . . . . . . . . . 13
⊢
(((((𝐹:(0..^2)–1-1→dom 𝐼 ∧ ((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)})) ∧ 𝐺 ∈ USGraph) ∧ 𝑃:(0...2)⟶𝑉) ∧ 𝑥 = (𝑃‘0)) → ((𝑃‘1) ∈ (𝑉 ∖ {𝑥}) ↔ (𝑃‘1) ∈ (𝑉 ∖ {(𝑃‘0)}))) | 
| 37 | 32, 36 | mpbird 257 | . . . . . . . . . . . 12
⊢
(((((𝐹:(0..^2)–1-1→dom 𝐼 ∧ ((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)})) ∧ 𝐺 ∈ USGraph) ∧ 𝑃:(0...2)⟶𝑉) ∧ 𝑥 = (𝑃‘0)) → (𝑃‘1) ∈ (𝑉 ∖ {𝑥})) | 
| 38 |  | 2re 12341 | . . . . . . . . . . . . . . . . . . . 20
⊢ 2 ∈
ℝ | 
| 39 | 38 | leidi 11798 | . . . . . . . . . . . . . . . . . . 19
⊢ 2 ≤
2 | 
| 40 |  | elfz2nn0 13659 | . . . . . . . . . . . . . . . . . . 19
⊢ (2 ∈
(0...2) ↔ (2 ∈ ℕ0 ∧ 2 ∈ ℕ0
∧ 2 ≤ 2)) | 
| 41 | 2, 2, 39, 40 | mpbir3an 1341 | . . . . . . . . . . . . . . . . . 18
⊢ 2 ∈
(0...2) | 
| 42 |  | ffvelcdm 7100 | . . . . . . . . . . . . . . . . . 18
⊢ ((𝑃:(0...2)⟶𝑉 ∧ 2 ∈ (0...2)) →
(𝑃‘2) ∈ 𝑉) | 
| 43 | 41, 42 | mpan2 691 | . . . . . . . . . . . . . . . . 17
⊢ (𝑃:(0...2)⟶𝑉 → (𝑃‘2) ∈ 𝑉) | 
| 44 | 43 | adantl 481 | . . . . . . . . . . . . . . . 16
⊢ ((((𝐹:(0..^2)–1-1→dom 𝐼 ∧ ((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)})) ∧ 𝐺 ∈ USGraph) ∧ 𝑃:(0...2)⟶𝑉) → (𝑃‘2) ∈ 𝑉) | 
| 45 | 24 | usgrf1 29190 | . . . . . . . . . . . . . . . . . . . . . 22
⊢ (𝐺 ∈ USGraph → 𝐼:dom 𝐼–1-1→ran 𝐼) | 
| 46 | 45 | ad2antlr 727 | . . . . . . . . . . . . . . . . . . . . 21
⊢ ((((𝐹:(0..^2)–1-1→dom 𝐼 ∧ ((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)})) ∧ 𝐺 ∈ USGraph) ∧ 𝑃:(0...2)⟶𝑉) → 𝐼:dom 𝐼–1-1→ran 𝐼) | 
| 47 |  | simpl 482 | . . . . . . . . . . . . . . . . . . . . . 22
⊢ ((𝐹:(0..^2)–1-1→dom 𝐼 ∧ ((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)})) → 𝐹:(0..^2)–1-1→dom 𝐼) | 
| 48 | 47 | ad2antrr 726 | . . . . . . . . . . . . . . . . . . . . 21
⊢ ((((𝐹:(0..^2)–1-1→dom 𝐼 ∧ ((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)})) ∧ 𝐺 ∈ USGraph) ∧ 𝑃:(0...2)⟶𝑉) → 𝐹:(0..^2)–1-1→dom 𝐼) | 
| 49 | 46, 48 | jca 511 | . . . . . . . . . . . . . . . . . . . 20
⊢ ((((𝐹:(0..^2)–1-1→dom 𝐼 ∧ ((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)})) ∧ 𝐺 ∈ USGraph) ∧ 𝑃:(0...2)⟶𝑉) → (𝐼:dom 𝐼–1-1→ran 𝐼 ∧ 𝐹:(0..^2)–1-1→dom 𝐼)) | 
| 50 |  | 2nn 12340 | . . . . . . . . . . . . . . . . . . . . . . 23
⊢ 2 ∈
ℕ | 
| 51 |  | lbfzo0 13740 | . . . . . . . . . . . . . . . . . . . . . . 23
⊢ (0 ∈
(0..^2) ↔ 2 ∈ ℕ) | 
| 52 | 50, 51 | mpbir 231 | . . . . . . . . . . . . . . . . . . . . . 22
⊢ 0 ∈
(0..^2) | 
| 53 |  | 1lt2 12438 | . . . . . . . . . . . . . . . . . . . . . . 23
⊢ 1 <
2 | 
| 54 |  | elfzo0 13741 | . . . . . . . . . . . . . . . . . . . . . . 23
⊢ (1 ∈
(0..^2) ↔ (1 ∈ ℕ0 ∧ 2 ∈ ℕ ∧ 1
< 2)) | 
| 55 | 9, 50, 53, 54 | mpbir3an 1341 | . . . . . . . . . . . . . . . . . . . . . 22
⊢ 1 ∈
(0..^2) | 
| 56 | 52, 55 | pm3.2i 470 | . . . . . . . . . . . . . . . . . . . . 21
⊢ (0 ∈
(0..^2) ∧ 1 ∈ (0..^2)) | 
| 57 | 56 | a1i 11 | . . . . . . . . . . . . . . . . . . . 20
⊢ ((((𝐹:(0..^2)–1-1→dom 𝐼 ∧ ((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)})) ∧ 𝐺 ∈ USGraph) ∧ 𝑃:(0...2)⟶𝑉) → (0 ∈ (0..^2) ∧ 1 ∈
(0..^2))) | 
| 58 |  | 0ne1 12338 | . . . . . . . . . . . . . . . . . . . . 21
⊢ 0 ≠
1 | 
| 59 | 58 | a1i 11 | . . . . . . . . . . . . . . . . . . . 20
⊢ ((((𝐹:(0..^2)–1-1→dom 𝐼 ∧ ((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)})) ∧ 𝐺 ∈ USGraph) ∧ 𝑃:(0...2)⟶𝑉) → 0 ≠ 1) | 
| 60 | 49, 57, 59 | 3jca 1128 | . . . . . . . . . . . . . . . . . . 19
⊢ ((((𝐹:(0..^2)–1-1→dom 𝐼 ∧ ((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)})) ∧ 𝐺 ∈ USGraph) ∧ 𝑃:(0...2)⟶𝑉) → ((𝐼:dom 𝐼–1-1→ran 𝐼 ∧ 𝐹:(0..^2)–1-1→dom 𝐼) ∧ (0 ∈ (0..^2) ∧ 1 ∈
(0..^2)) ∧ 0 ≠ 1)) | 
| 61 |  | simpr 484 | . . . . . . . . . . . . . . . . . . . 20
⊢ ((𝐹:(0..^2)–1-1→dom 𝐼 ∧ ((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)})) → ((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)})) | 
| 62 | 61 | ad2antrr 726 | . . . . . . . . . . . . . . . . . . 19
⊢ ((((𝐹:(0..^2)–1-1→dom 𝐼 ∧ ((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)})) ∧ 𝐺 ∈ USGraph) ∧ 𝑃:(0...2)⟶𝑉) → ((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)})) | 
| 63 |  | 2f1fvneq 7281 | . . . . . . . . . . . . . . . . . . 19
⊢ (((𝐼:dom 𝐼–1-1→ran 𝐼 ∧ 𝐹:(0..^2)–1-1→dom 𝐼) ∧ (0 ∈ (0..^2) ∧ 1 ∈
(0..^2)) ∧ 0 ≠ 1) → (((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)}) → {(𝑃‘0), (𝑃‘1)} ≠ {(𝑃‘1), (𝑃‘2)})) | 
| 64 | 60, 62, 63 | sylc 65 | . . . . . . . . . . . . . . . . . 18
⊢ ((((𝐹:(0..^2)–1-1→dom 𝐼 ∧ ((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)})) ∧ 𝐺 ∈ USGraph) ∧ 𝑃:(0...2)⟶𝑉) → {(𝑃‘0), (𝑃‘1)} ≠ {(𝑃‘1), (𝑃‘2)}) | 
| 65 |  | necom 2993 | . . . . . . . . . . . . . . . . . . 19
⊢ ((𝑃‘2) ≠ (𝑃‘0) ↔ (𝑃‘0) ≠ (𝑃‘2)) | 
| 66 |  | fvex 6918 | . . . . . . . . . . . . . . . . . . . . 21
⊢ (𝑃‘0) ∈
V | 
| 67 |  | fvex 6918 | . . . . . . . . . . . . . . . . . . . . 21
⊢ (𝑃‘2) ∈
V | 
| 68 | 66, 17, 67 | 3pm3.2i 1339 | . . . . . . . . . . . . . . . . . . . 20
⊢ ((𝑃‘0) ∈ V ∧ (𝑃‘1) ∈ V ∧ (𝑃‘2) ∈
V) | 
| 69 |  | fvexd 6920 | . . . . . . . . . . . . . . . . . . . . . . 23
⊢ (((𝐹:(0..^2)–1-1→dom 𝐼 ∧ ((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)})) ∧ 𝐺 ∈ USGraph) → (𝑃‘0) ∈ V) | 
| 70 |  | simpl 482 | . . . . . . . . . . . . . . . . . . . . . . . 24
⊢ (((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)}) → (𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)}) | 
| 71 | 70 | ad2antlr 727 | . . . . . . . . . . . . . . . . . . . . . . 23
⊢ (((𝐹:(0..^2)–1-1→dom 𝐼 ∧ ((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)})) ∧ 𝐺 ∈ USGraph) → (𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)}) | 
| 72 | 16, 69, 71 | jca31 514 | . . . . . . . . . . . . . . . . . . . . . 22
⊢ (((𝐹:(0..^2)–1-1→dom 𝐼 ∧ ((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)})) ∧ 𝐺 ∈ USGraph) → ((𝐺 ∈ USGraph ∧ (𝑃‘0) ∈ V) ∧ (𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)})) | 
| 73 | 72 | adantr 480 | . . . . . . . . . . . . . . . . . . . . 21
⊢ ((((𝐹:(0..^2)–1-1→dom 𝐼 ∧ ((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)})) ∧ 𝐺 ∈ USGraph) ∧ 𝑃:(0...2)⟶𝑉) → ((𝐺 ∈ USGraph ∧ (𝑃‘0) ∈ V) ∧ (𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)})) | 
| 74 | 24 | usgrnloopv 29218 | . . . . . . . . . . . . . . . . . . . . . 22
⊢ ((𝐺 ∈ USGraph ∧ (𝑃‘0) ∈ V) →
((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} → (𝑃‘0) ≠ (𝑃‘1))) | 
| 75 | 74 | imp 406 | . . . . . . . . . . . . . . . . . . . . 21
⊢ (((𝐺 ∈ USGraph ∧ (𝑃‘0) ∈ V) ∧ (𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)}) → (𝑃‘0) ≠ (𝑃‘1)) | 
| 76 | 73, 75 | syl 17 | . . . . . . . . . . . . . . . . . . . 20
⊢ ((((𝐹:(0..^2)–1-1→dom 𝐼 ∧ ((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)})) ∧ 𝐺 ∈ USGraph) ∧ 𝑃:(0...2)⟶𝑉) → (𝑃‘0) ≠ (𝑃‘1)) | 
| 77 |  | pr1nebg 4857 | . . . . . . . . . . . . . . . . . . . 20
⊢ ((((𝑃‘0) ∈ V ∧ (𝑃‘1) ∈ V ∧ (𝑃‘2) ∈ V) ∧ (𝑃‘0) ≠ (𝑃‘1)) → ((𝑃‘0) ≠ (𝑃‘2) ↔ {(𝑃‘0), (𝑃‘1)} ≠ {(𝑃‘1), (𝑃‘2)})) | 
| 78 | 68, 76, 77 | sylancr 587 | . . . . . . . . . . . . . . . . . . 19
⊢ ((((𝐹:(0..^2)–1-1→dom 𝐼 ∧ ((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)})) ∧ 𝐺 ∈ USGraph) ∧ 𝑃:(0...2)⟶𝑉) → ((𝑃‘0) ≠ (𝑃‘2) ↔ {(𝑃‘0), (𝑃‘1)} ≠ {(𝑃‘1), (𝑃‘2)})) | 
| 79 | 65, 78 | bitrid 283 | . . . . . . . . . . . . . . . . . 18
⊢ ((((𝐹:(0..^2)–1-1→dom 𝐼 ∧ ((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)})) ∧ 𝐺 ∈ USGraph) ∧ 𝑃:(0...2)⟶𝑉) → ((𝑃‘2) ≠ (𝑃‘0) ↔ {(𝑃‘0), (𝑃‘1)} ≠ {(𝑃‘1), (𝑃‘2)})) | 
| 80 | 64, 79 | mpbird 257 | . . . . . . . . . . . . . . . . 17
⊢ ((((𝐹:(0..^2)–1-1→dom 𝐼 ∧ ((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)})) ∧ 𝐺 ∈ USGraph) ∧ 𝑃:(0...2)⟶𝑉) → (𝑃‘2) ≠ (𝑃‘0)) | 
| 81 |  | fvexd 6920 | . . . . . . . . . . . . . . . . . . . 20
⊢ (((𝐹:(0..^2)–1-1→dom 𝐼 ∧ ((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)})) ∧ 𝐺 ∈ USGraph) → (𝑃‘2) ∈ V) | 
| 82 |  | prcom 4731 | . . . . . . . . . . . . . . . . . . . . . . . 24
⊢ {(𝑃‘1), (𝑃‘2)} = {(𝑃‘2), (𝑃‘1)} | 
| 83 | 82 | eqeq2i 2749 | . . . . . . . . . . . . . . . . . . . . . . 23
⊢ ((𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)} ↔ (𝐼‘(𝐹‘1)) = {(𝑃‘2), (𝑃‘1)}) | 
| 84 | 83 | biimpi 216 | . . . . . . . . . . . . . . . . . . . . . 22
⊢ ((𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)} → (𝐼‘(𝐹‘1)) = {(𝑃‘2), (𝑃‘1)}) | 
| 85 | 84 | adantl 481 | . . . . . . . . . . . . . . . . . . . . 21
⊢ (((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)}) → (𝐼‘(𝐹‘1)) = {(𝑃‘2), (𝑃‘1)}) | 
| 86 | 85 | ad2antlr 727 | . . . . . . . . . . . . . . . . . . . 20
⊢ (((𝐹:(0..^2)–1-1→dom 𝐼 ∧ ((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)})) ∧ 𝐺 ∈ USGraph) → (𝐼‘(𝐹‘1)) = {(𝑃‘2), (𝑃‘1)}) | 
| 87 | 16, 81, 86 | jca31 514 | . . . . . . . . . . . . . . . . . . 19
⊢ (((𝐹:(0..^2)–1-1→dom 𝐼 ∧ ((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)})) ∧ 𝐺 ∈ USGraph) → ((𝐺 ∈ USGraph ∧ (𝑃‘2) ∈ V) ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘2), (𝑃‘1)})) | 
| 88 | 87 | adantr 480 | . . . . . . . . . . . . . . . . . 18
⊢ ((((𝐹:(0..^2)–1-1→dom 𝐼 ∧ ((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)})) ∧ 𝐺 ∈ USGraph) ∧ 𝑃:(0...2)⟶𝑉) → ((𝐺 ∈ USGraph ∧ (𝑃‘2) ∈ V) ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘2), (𝑃‘1)})) | 
| 89 | 24 | usgrnloopv 29218 | . . . . . . . . . . . . . . . . . . 19
⊢ ((𝐺 ∈ USGraph ∧ (𝑃‘2) ∈ V) →
((𝐼‘(𝐹‘1)) = {(𝑃‘2), (𝑃‘1)} → (𝑃‘2) ≠ (𝑃‘1))) | 
| 90 | 89 | imp 406 | . . . . . . . . . . . . . . . . . 18
⊢ (((𝐺 ∈ USGraph ∧ (𝑃‘2) ∈ V) ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘2), (𝑃‘1)}) → (𝑃‘2) ≠ (𝑃‘1)) | 
| 91 | 88, 90 | syl 17 | . . . . . . . . . . . . . . . . 17
⊢ ((((𝐹:(0..^2)–1-1→dom 𝐼 ∧ ((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)})) ∧ 𝐺 ∈ USGraph) ∧ 𝑃:(0...2)⟶𝑉) → (𝑃‘2) ≠ (𝑃‘1)) | 
| 92 | 80, 91 | nelprd 4656 | . . . . . . . . . . . . . . . 16
⊢ ((((𝐹:(0..^2)–1-1→dom 𝐼 ∧ ((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)})) ∧ 𝐺 ∈ USGraph) ∧ 𝑃:(0...2)⟶𝑉) → ¬ (𝑃‘2) ∈ {(𝑃‘0), (𝑃‘1)}) | 
| 93 | 44, 92 | eldifd 3961 | . . . . . . . . . . . . . . 15
⊢ ((((𝐹:(0..^2)–1-1→dom 𝐼 ∧ ((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)})) ∧ 𝐺 ∈ USGraph) ∧ 𝑃:(0...2)⟶𝑉) → (𝑃‘2) ∈ (𝑉 ∖ {(𝑃‘0), (𝑃‘1)})) | 
| 94 | 93 | ad2antrr 726 | . . . . . . . . . . . . . 14
⊢
((((((𝐹:(0..^2)–1-1→dom 𝐼 ∧ ((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)})) ∧ 𝐺 ∈ USGraph) ∧ 𝑃:(0...2)⟶𝑉) ∧ 𝑥 = (𝑃‘0)) ∧ 𝑦 = (𝑃‘1)) → (𝑃‘2) ∈ (𝑉 ∖ {(𝑃‘0), (𝑃‘1)})) | 
| 95 |  | preq12 4734 | . . . . . . . . . . . . . . . . 17
⊢ ((𝑥 = (𝑃‘0) ∧ 𝑦 = (𝑃‘1)) → {𝑥, 𝑦} = {(𝑃‘0), (𝑃‘1)}) | 
| 96 | 95 | difeq2d 4125 | . . . . . . . . . . . . . . . 16
⊢ ((𝑥 = (𝑃‘0) ∧ 𝑦 = (𝑃‘1)) → (𝑉 ∖ {𝑥, 𝑦}) = (𝑉 ∖ {(𝑃‘0), (𝑃‘1)})) | 
| 97 | 96 | eleq2d 2826 | . . . . . . . . . . . . . . 15
⊢ ((𝑥 = (𝑃‘0) ∧ 𝑦 = (𝑃‘1)) → ((𝑃‘2) ∈ (𝑉 ∖ {𝑥, 𝑦}) ↔ (𝑃‘2) ∈ (𝑉 ∖ {(𝑃‘0), (𝑃‘1)}))) | 
| 98 | 97 | adantll 714 | . . . . . . . . . . . . . 14
⊢
((((((𝐹:(0..^2)–1-1→dom 𝐼 ∧ ((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)})) ∧ 𝐺 ∈ USGraph) ∧ 𝑃:(0...2)⟶𝑉) ∧ 𝑥 = (𝑃‘0)) ∧ 𝑦 = (𝑃‘1)) → ((𝑃‘2) ∈ (𝑉 ∖ {𝑥, 𝑦}) ↔ (𝑃‘2) ∈ (𝑉 ∖ {(𝑃‘0), (𝑃‘1)}))) | 
| 99 | 94, 98 | mpbird 257 | . . . . . . . . . . . . 13
⊢
((((((𝐹:(0..^2)–1-1→dom 𝐼 ∧ ((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)})) ∧ 𝐺 ∈ USGraph) ∧ 𝑃:(0...2)⟶𝑉) ∧ 𝑥 = (𝑃‘0)) ∧ 𝑦 = (𝑃‘1)) → (𝑃‘2) ∈ (𝑉 ∖ {𝑥, 𝑦})) | 
| 100 |  | eqcom 2743 | . . . . . . . . . . . . . . . . . . . 20
⊢ (𝑥 = (𝑃‘0) ↔ (𝑃‘0) = 𝑥) | 
| 101 |  | eqcom 2743 | . . . . . . . . . . . . . . . . . . . 20
⊢ (𝑦 = (𝑃‘1) ↔ (𝑃‘1) = 𝑦) | 
| 102 |  | eqcom 2743 | . . . . . . . . . . . . . . . . . . . 20
⊢ (𝑧 = (𝑃‘2) ↔ (𝑃‘2) = 𝑧) | 
| 103 | 100, 101,
102 | 3anbi123i 1155 | . . . . . . . . . . . . . . . . . . 19
⊢ ((𝑥 = (𝑃‘0) ∧ 𝑦 = (𝑃‘1) ∧ 𝑧 = (𝑃‘2)) ↔ ((𝑃‘0) = 𝑥 ∧ (𝑃‘1) = 𝑦 ∧ (𝑃‘2) = 𝑧)) | 
| 104 | 103 | biimpi 216 | . . . . . . . . . . . . . . . . . 18
⊢ ((𝑥 = (𝑃‘0) ∧ 𝑦 = (𝑃‘1) ∧ 𝑧 = (𝑃‘2)) → ((𝑃‘0) = 𝑥 ∧ (𝑃‘1) = 𝑦 ∧ (𝑃‘2) = 𝑧)) | 
| 105 | 104 | ad4ant123 1172 | . . . . . . . . . . . . . . . . 17
⊢ ((((𝑥 = (𝑃‘0) ∧ 𝑦 = (𝑃‘1)) ∧ 𝑧 = (𝑃‘2)) ∧ ((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)})) → ((𝑃‘0) = 𝑥 ∧ (𝑃‘1) = 𝑦 ∧ (𝑃‘2) = 𝑧)) | 
| 106 | 100 | biimpi 216 | . . . . . . . . . . . . . . . . . . . . . 22
⊢ (𝑥 = (𝑃‘0) → (𝑃‘0) = 𝑥) | 
| 107 | 106 | ad2antrr 726 | . . . . . . . . . . . . . . . . . . . . 21
⊢ (((𝑥 = (𝑃‘0) ∧ 𝑦 = (𝑃‘1)) ∧ 𝑧 = (𝑃‘2)) → (𝑃‘0) = 𝑥) | 
| 108 | 101 | biimpi 216 | . . . . . . . . . . . . . . . . . . . . . 22
⊢ (𝑦 = (𝑃‘1) → (𝑃‘1) = 𝑦) | 
| 109 | 108 | ad2antlr 727 | . . . . . . . . . . . . . . . . . . . . 21
⊢ (((𝑥 = (𝑃‘0) ∧ 𝑦 = (𝑃‘1)) ∧ 𝑧 = (𝑃‘2)) → (𝑃‘1) = 𝑦) | 
| 110 | 107, 109 | preq12d 4740 | . . . . . . . . . . . . . . . . . . . 20
⊢ (((𝑥 = (𝑃‘0) ∧ 𝑦 = (𝑃‘1)) ∧ 𝑧 = (𝑃‘2)) → {(𝑃‘0), (𝑃‘1)} = {𝑥, 𝑦}) | 
| 111 | 110 | eqeq2d 2747 | . . . . . . . . . . . . . . . . . . 19
⊢ (((𝑥 = (𝑃‘0) ∧ 𝑦 = (𝑃‘1)) ∧ 𝑧 = (𝑃‘2)) → ((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ↔ (𝐼‘(𝐹‘0)) = {𝑥, 𝑦})) | 
| 112 | 102 | biimpi 216 | . . . . . . . . . . . . . . . . . . . . . 22
⊢ (𝑧 = (𝑃‘2) → (𝑃‘2) = 𝑧) | 
| 113 | 112 | adantl 481 | . . . . . . . . . . . . . . . . . . . . 21
⊢ (((𝑥 = (𝑃‘0) ∧ 𝑦 = (𝑃‘1)) ∧ 𝑧 = (𝑃‘2)) → (𝑃‘2) = 𝑧) | 
| 114 | 109, 113 | preq12d 4740 | . . . . . . . . . . . . . . . . . . . 20
⊢ (((𝑥 = (𝑃‘0) ∧ 𝑦 = (𝑃‘1)) ∧ 𝑧 = (𝑃‘2)) → {(𝑃‘1), (𝑃‘2)} = {𝑦, 𝑧}) | 
| 115 | 114 | eqeq2d 2747 | . . . . . . . . . . . . . . . . . . 19
⊢ (((𝑥 = (𝑃‘0) ∧ 𝑦 = (𝑃‘1)) ∧ 𝑧 = (𝑃‘2)) → ((𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)} ↔ (𝐼‘(𝐹‘1)) = {𝑦, 𝑧})) | 
| 116 | 111, 115 | anbi12d 632 | . . . . . . . . . . . . . . . . . 18
⊢ (((𝑥 = (𝑃‘0) ∧ 𝑦 = (𝑃‘1)) ∧ 𝑧 = (𝑃‘2)) → (((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)}) ↔ ((𝐼‘(𝐹‘0)) = {𝑥, 𝑦} ∧ (𝐼‘(𝐹‘1)) = {𝑦, 𝑧}))) | 
| 117 | 116 | biimpa 476 | . . . . . . . . . . . . . . . . 17
⊢ ((((𝑥 = (𝑃‘0) ∧ 𝑦 = (𝑃‘1)) ∧ 𝑧 = (𝑃‘2)) ∧ ((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)})) → ((𝐼‘(𝐹‘0)) = {𝑥, 𝑦} ∧ (𝐼‘(𝐹‘1)) = {𝑦, 𝑧})) | 
| 118 | 105, 117 | jca 511 | . . . . . . . . . . . . . . . 16
⊢ ((((𝑥 = (𝑃‘0) ∧ 𝑦 = (𝑃‘1)) ∧ 𝑧 = (𝑃‘2)) ∧ ((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)})) → (((𝑃‘0) = 𝑥 ∧ (𝑃‘1) = 𝑦 ∧ (𝑃‘2) = 𝑧) ∧ ((𝐼‘(𝐹‘0)) = {𝑥, 𝑦} ∧ (𝐼‘(𝐹‘1)) = {𝑦, 𝑧}))) | 
| 119 | 118 | exp41 434 | . . . . . . . . . . . . . . 15
⊢ (𝑥 = (𝑃‘0) → (𝑦 = (𝑃‘1) → (𝑧 = (𝑃‘2) → (((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)}) → (((𝑃‘0) = 𝑥 ∧ (𝑃‘1) = 𝑦 ∧ (𝑃‘2) = 𝑧) ∧ ((𝐼‘(𝐹‘0)) = {𝑥, 𝑦} ∧ (𝐼‘(𝐹‘1)) = {𝑦, 𝑧})))))) | 
| 120 | 119 | adantl 481 | . . . . . . . . . . . . . 14
⊢
(((((𝐹:(0..^2)–1-1→dom 𝐼 ∧ ((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)})) ∧ 𝐺 ∈ USGraph) ∧ 𝑃:(0...2)⟶𝑉) ∧ 𝑥 = (𝑃‘0)) → (𝑦 = (𝑃‘1) → (𝑧 = (𝑃‘2) → (((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)}) → (((𝑃‘0) = 𝑥 ∧ (𝑃‘1) = 𝑦 ∧ (𝑃‘2) = 𝑧) ∧ ((𝐼‘(𝐹‘0)) = {𝑥, 𝑦} ∧ (𝐼‘(𝐹‘1)) = {𝑦, 𝑧})))))) | 
| 121 | 120 | imp31 417 | . . . . . . . . . . . . 13
⊢
(((((((𝐹:(0..^2)–1-1→dom 𝐼 ∧ ((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)})) ∧ 𝐺 ∈ USGraph) ∧ 𝑃:(0...2)⟶𝑉) ∧ 𝑥 = (𝑃‘0)) ∧ 𝑦 = (𝑃‘1)) ∧ 𝑧 = (𝑃‘2)) → (((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)}) → (((𝑃‘0) = 𝑥 ∧ (𝑃‘1) = 𝑦 ∧ (𝑃‘2) = 𝑧) ∧ ((𝐼‘(𝐹‘0)) = {𝑥, 𝑦} ∧ (𝐼‘(𝐹‘1)) = {𝑦, 𝑧})))) | 
| 122 | 99, 121 | rspcimedv 3612 | . . . . . . . . . . . 12
⊢
((((((𝐹:(0..^2)–1-1→dom 𝐼 ∧ ((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)})) ∧ 𝐺 ∈ USGraph) ∧ 𝑃:(0...2)⟶𝑉) ∧ 𝑥 = (𝑃‘0)) ∧ 𝑦 = (𝑃‘1)) → (((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)}) → ∃𝑧 ∈ (𝑉 ∖ {𝑥, 𝑦})(((𝑃‘0) = 𝑥 ∧ (𝑃‘1) = 𝑦 ∧ (𝑃‘2) = 𝑧) ∧ ((𝐼‘(𝐹‘0)) = {𝑥, 𝑦} ∧ (𝐼‘(𝐹‘1)) = {𝑦, 𝑧})))) | 
| 123 | 37, 122 | rspcimedv 3612 | . . . . . . . . . . 11
⊢
(((((𝐹:(0..^2)–1-1→dom 𝐼 ∧ ((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)})) ∧ 𝐺 ∈ USGraph) ∧ 𝑃:(0...2)⟶𝑉) ∧ 𝑥 = (𝑃‘0)) → (((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)}) → ∃𝑦 ∈ (𝑉 ∖ {𝑥})∃𝑧 ∈ (𝑉 ∖ {𝑥, 𝑦})(((𝑃‘0) = 𝑥 ∧ (𝑃‘1) = 𝑦 ∧ (𝑃‘2) = 𝑧) ∧ ((𝐼‘(𝐹‘0)) = {𝑥, 𝑦} ∧ (𝐼‘(𝐹‘1)) = {𝑦, 𝑧})))) | 
| 124 | 8, 123 | rspcimedv 3612 | . . . . . . . . . 10
⊢ ((((𝐹:(0..^2)–1-1→dom 𝐼 ∧ ((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)})) ∧ 𝐺 ∈ USGraph) ∧ 𝑃:(0...2)⟶𝑉) → (((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)}) → ∃𝑥 ∈ 𝑉 ∃𝑦 ∈ (𝑉 ∖ {𝑥})∃𝑧 ∈ (𝑉 ∖ {𝑥, 𝑦})(((𝑃‘0) = 𝑥 ∧ (𝑃‘1) = 𝑦 ∧ (𝑃‘2) = 𝑧) ∧ ((𝐼‘(𝐹‘0)) = {𝑥, 𝑦} ∧ (𝐼‘(𝐹‘1)) = {𝑦, 𝑧})))) | 
| 125 | 124 | exp41 434 | . . . . . . . . 9
⊢ (𝐹:(0..^2)–1-1→dom 𝐼 → (((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)}) → (𝐺 ∈ USGraph → (𝑃:(0...2)⟶𝑉 → (((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)}) → ∃𝑥 ∈ 𝑉 ∃𝑦 ∈ (𝑉 ∖ {𝑥})∃𝑧 ∈ (𝑉 ∖ {𝑥, 𝑦})(((𝑃‘0) = 𝑥 ∧ (𝑃‘1) = 𝑦 ∧ (𝑃‘2) = 𝑧) ∧ ((𝐼‘(𝐹‘0)) = {𝑥, 𝑦} ∧ (𝐼‘(𝐹‘1)) = {𝑦, 𝑧}))))))) | 
| 126 | 125 | com15 101 | . . . . . . . 8
⊢ (((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)}) → (((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)}) → (𝐺 ∈ USGraph → (𝑃:(0...2)⟶𝑉 → (𝐹:(0..^2)–1-1→dom 𝐼 → ∃𝑥 ∈ 𝑉 ∃𝑦 ∈ (𝑉 ∖ {𝑥})∃𝑧 ∈ (𝑉 ∖ {𝑥, 𝑦})(((𝑃‘0) = 𝑥 ∧ (𝑃‘1) = 𝑦 ∧ (𝑃‘2) = 𝑧) ∧ ((𝐼‘(𝐹‘0)) = {𝑥, 𝑦} ∧ (𝐼‘(𝐹‘1)) = {𝑦, 𝑧}))))))) | 
| 127 | 126 | pm2.43i 52 | . . . . . . 7
⊢ (((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)}) → (𝐺 ∈ USGraph → (𝑃:(0...2)⟶𝑉 → (𝐹:(0..^2)–1-1→dom 𝐼 → ∃𝑥 ∈ 𝑉 ∃𝑦 ∈ (𝑉 ∖ {𝑥})∃𝑧 ∈ (𝑉 ∖ {𝑥, 𝑦})(((𝑃‘0) = 𝑥 ∧ (𝑃‘1) = 𝑦 ∧ (𝑃‘2) = 𝑧) ∧ ((𝐼‘(𝐹‘0)) = {𝑥, 𝑦} ∧ (𝐼‘(𝐹‘1)) = {𝑦, 𝑧})))))) | 
| 128 | 127 | com12 32 | . . . . . 6
⊢ (𝐺 ∈ USGraph → (((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)}) → (𝑃:(0...2)⟶𝑉 → (𝐹:(0..^2)–1-1→dom 𝐼 → ∃𝑥 ∈ 𝑉 ∃𝑦 ∈ (𝑉 ∖ {𝑥})∃𝑧 ∈ (𝑉 ∖ {𝑥, 𝑦})(((𝑃‘0) = 𝑥 ∧ (𝑃‘1) = 𝑦 ∧ (𝑃‘2) = 𝑧) ∧ ((𝐼‘(𝐹‘0)) = {𝑥, 𝑦} ∧ (𝐼‘(𝐹‘1)) = {𝑦, 𝑧})))))) | 
| 129 | 128 | adantr 480 | . . . . 5
⊢ ((𝐺 ∈ USGraph ∧
(♯‘𝐹) = 2)
→ (((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)}) → (𝑃:(0...2)⟶𝑉 → (𝐹:(0..^2)–1-1→dom 𝐼 → ∃𝑥 ∈ 𝑉 ∃𝑦 ∈ (𝑉 ∖ {𝑥})∃𝑧 ∈ (𝑉 ∖ {𝑥, 𝑦})(((𝑃‘0) = 𝑥 ∧ (𝑃‘1) = 𝑦 ∧ (𝑃‘2) = 𝑧) ∧ ((𝐼‘(𝐹‘0)) = {𝑥, 𝑦} ∧ (𝐼‘(𝐹‘1)) = {𝑦, 𝑧})))))) | 
| 130 |  | oveq2 7440 | . . . . . . . 8
⊢
((♯‘𝐹) =
2 → (0..^(♯‘𝐹)) = (0..^2)) | 
| 131 | 130 | raleqdv 3325 | . . . . . . 7
⊢
((♯‘𝐹) =
2 → (∀𝑖 ∈
(0..^(♯‘𝐹))(𝐼‘(𝐹‘𝑖)) = {(𝑃‘𝑖), (𝑃‘(𝑖 + 1))} ↔ ∀𝑖 ∈ (0..^2)(𝐼‘(𝐹‘𝑖)) = {(𝑃‘𝑖), (𝑃‘(𝑖 + 1))})) | 
| 132 |  | fzo0to2pr 13790 | . . . . . . . . 9
⊢ (0..^2) =
{0, 1} | 
| 133 | 132 | raleqi 3323 | . . . . . . . 8
⊢
(∀𝑖 ∈
(0..^2)(𝐼‘(𝐹‘𝑖)) = {(𝑃‘𝑖), (𝑃‘(𝑖 + 1))} ↔ ∀𝑖 ∈ {0, 1} (𝐼‘(𝐹‘𝑖)) = {(𝑃‘𝑖), (𝑃‘(𝑖 + 1))}) | 
| 134 |  | 2wlklem 29686 | . . . . . . . 8
⊢
(∀𝑖 ∈
{0, 1} (𝐼‘(𝐹‘𝑖)) = {(𝑃‘𝑖), (𝑃‘(𝑖 + 1))} ↔ ((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)})) | 
| 135 | 133, 134 | bitri 275 | . . . . . . 7
⊢
(∀𝑖 ∈
(0..^2)(𝐼‘(𝐹‘𝑖)) = {(𝑃‘𝑖), (𝑃‘(𝑖 + 1))} ↔ ((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)})) | 
| 136 | 131, 135 | bitrdi 287 | . . . . . 6
⊢
((♯‘𝐹) =
2 → (∀𝑖 ∈
(0..^(♯‘𝐹))(𝐼‘(𝐹‘𝑖)) = {(𝑃‘𝑖), (𝑃‘(𝑖 + 1))} ↔ ((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)}))) | 
| 137 | 136 | adantl 481 | . . . . 5
⊢ ((𝐺 ∈ USGraph ∧
(♯‘𝐹) = 2)
→ (∀𝑖 ∈
(0..^(♯‘𝐹))(𝐼‘(𝐹‘𝑖)) = {(𝑃‘𝑖), (𝑃‘(𝑖 + 1))} ↔ ((𝐼‘(𝐹‘0)) = {(𝑃‘0), (𝑃‘1)} ∧ (𝐼‘(𝐹‘1)) = {(𝑃‘1), (𝑃‘2)}))) | 
| 138 |  | oveq2 7440 | . . . . . . . 8
⊢
((♯‘𝐹) =
2 → (0...(♯‘𝐹)) = (0...2)) | 
| 139 | 138 | feq2d 6721 | . . . . . . 7
⊢
((♯‘𝐹) =
2 → (𝑃:(0...(♯‘𝐹))⟶𝑉 ↔ 𝑃:(0...2)⟶𝑉)) | 
| 140 | 139 | adantl 481 | . . . . . 6
⊢ ((𝐺 ∈ USGraph ∧
(♯‘𝐹) = 2)
→ (𝑃:(0...(♯‘𝐹))⟶𝑉 ↔ 𝑃:(0...2)⟶𝑉)) | 
| 141 |  | f1eq2 6799 | . . . . . . . . 9
⊢
((0..^(♯‘𝐹)) = (0..^2) → (𝐹:(0..^(♯‘𝐹))–1-1→dom 𝐼 ↔ 𝐹:(0..^2)–1-1→dom 𝐼)) | 
| 142 | 130, 141 | syl 17 | . . . . . . . 8
⊢
((♯‘𝐹) =
2 → (𝐹:(0..^(♯‘𝐹))–1-1→dom 𝐼 ↔ 𝐹:(0..^2)–1-1→dom 𝐼)) | 
| 143 | 142 | imbi1d 341 | . . . . . . 7
⊢
((♯‘𝐹) =
2 → ((𝐹:(0..^(♯‘𝐹))–1-1→dom 𝐼 → ∃𝑥 ∈ 𝑉 ∃𝑦 ∈ (𝑉 ∖ {𝑥})∃𝑧 ∈ (𝑉 ∖ {𝑥, 𝑦})(((𝑃‘0) = 𝑥 ∧ (𝑃‘1) = 𝑦 ∧ (𝑃‘2) = 𝑧) ∧ ((𝐼‘(𝐹‘0)) = {𝑥, 𝑦} ∧ (𝐼‘(𝐹‘1)) = {𝑦, 𝑧}))) ↔ (𝐹:(0..^2)–1-1→dom 𝐼 → ∃𝑥 ∈ 𝑉 ∃𝑦 ∈ (𝑉 ∖ {𝑥})∃𝑧 ∈ (𝑉 ∖ {𝑥, 𝑦})(((𝑃‘0) = 𝑥 ∧ (𝑃‘1) = 𝑦 ∧ (𝑃‘2) = 𝑧) ∧ ((𝐼‘(𝐹‘0)) = {𝑥, 𝑦} ∧ (𝐼‘(𝐹‘1)) = {𝑦, 𝑧}))))) | 
| 144 | 143 | adantl 481 | . . . . . 6
⊢ ((𝐺 ∈ USGraph ∧
(♯‘𝐹) = 2)
→ ((𝐹:(0..^(♯‘𝐹))–1-1→dom 𝐼 → ∃𝑥 ∈ 𝑉 ∃𝑦 ∈ (𝑉 ∖ {𝑥})∃𝑧 ∈ (𝑉 ∖ {𝑥, 𝑦})(((𝑃‘0) = 𝑥 ∧ (𝑃‘1) = 𝑦 ∧ (𝑃‘2) = 𝑧) ∧ ((𝐼‘(𝐹‘0)) = {𝑥, 𝑦} ∧ (𝐼‘(𝐹‘1)) = {𝑦, 𝑧}))) ↔ (𝐹:(0..^2)–1-1→dom 𝐼 → ∃𝑥 ∈ 𝑉 ∃𝑦 ∈ (𝑉 ∖ {𝑥})∃𝑧 ∈ (𝑉 ∖ {𝑥, 𝑦})(((𝑃‘0) = 𝑥 ∧ (𝑃‘1) = 𝑦 ∧ (𝑃‘2) = 𝑧) ∧ ((𝐼‘(𝐹‘0)) = {𝑥, 𝑦} ∧ (𝐼‘(𝐹‘1)) = {𝑦, 𝑧}))))) | 
| 145 | 140, 144 | imbi12d 344 | . . . . 5
⊢ ((𝐺 ∈ USGraph ∧
(♯‘𝐹) = 2)
→ ((𝑃:(0...(♯‘𝐹))⟶𝑉 → (𝐹:(0..^(♯‘𝐹))–1-1→dom 𝐼 → ∃𝑥 ∈ 𝑉 ∃𝑦 ∈ (𝑉 ∖ {𝑥})∃𝑧 ∈ (𝑉 ∖ {𝑥, 𝑦})(((𝑃‘0) = 𝑥 ∧ (𝑃‘1) = 𝑦 ∧ (𝑃‘2) = 𝑧) ∧ ((𝐼‘(𝐹‘0)) = {𝑥, 𝑦} ∧ (𝐼‘(𝐹‘1)) = {𝑦, 𝑧})))) ↔ (𝑃:(0...2)⟶𝑉 → (𝐹:(0..^2)–1-1→dom 𝐼 → ∃𝑥 ∈ 𝑉 ∃𝑦 ∈ (𝑉 ∖ {𝑥})∃𝑧 ∈ (𝑉 ∖ {𝑥, 𝑦})(((𝑃‘0) = 𝑥 ∧ (𝑃‘1) = 𝑦 ∧ (𝑃‘2) = 𝑧) ∧ ((𝐼‘(𝐹‘0)) = {𝑥, 𝑦} ∧ (𝐼‘(𝐹‘1)) = {𝑦, 𝑧})))))) | 
| 146 | 129, 137,
145 | 3imtr4d 294 | . . . 4
⊢ ((𝐺 ∈ USGraph ∧
(♯‘𝐹) = 2)
→ (∀𝑖 ∈
(0..^(♯‘𝐹))(𝐼‘(𝐹‘𝑖)) = {(𝑃‘𝑖), (𝑃‘(𝑖 + 1))} → (𝑃:(0...(♯‘𝐹))⟶𝑉 → (𝐹:(0..^(♯‘𝐹))–1-1→dom 𝐼 → ∃𝑥 ∈ 𝑉 ∃𝑦 ∈ (𝑉 ∖ {𝑥})∃𝑧 ∈ (𝑉 ∖ {𝑥, 𝑦})(((𝑃‘0) = 𝑥 ∧ (𝑃‘1) = 𝑦 ∧ (𝑃‘2) = 𝑧) ∧ ((𝐼‘(𝐹‘0)) = {𝑥, 𝑦} ∧ (𝐼‘(𝐹‘1)) = {𝑦, 𝑧})))))) | 
| 147 | 146 | com14 96 | . . 3
⊢ (𝐹:(0..^(♯‘𝐹))–1-1→dom 𝐼 → (∀𝑖 ∈ (0..^(♯‘𝐹))(𝐼‘(𝐹‘𝑖)) = {(𝑃‘𝑖), (𝑃‘(𝑖 + 1))} → (𝑃:(0...(♯‘𝐹))⟶𝑉 → ((𝐺 ∈ USGraph ∧ (♯‘𝐹) = 2) → ∃𝑥 ∈ 𝑉 ∃𝑦 ∈ (𝑉 ∖ {𝑥})∃𝑧 ∈ (𝑉 ∖ {𝑥, 𝑦})(((𝑃‘0) = 𝑥 ∧ (𝑃‘1) = 𝑦 ∧ (𝑃‘2) = 𝑧) ∧ ((𝐼‘(𝐹‘0)) = {𝑥, 𝑦} ∧ (𝐼‘(𝐹‘1)) = {𝑦, 𝑧})))))) | 
| 148 | 147 | com23 86 | . 2
⊢ (𝐹:(0..^(♯‘𝐹))–1-1→dom 𝐼 → (𝑃:(0...(♯‘𝐹))⟶𝑉 → (∀𝑖 ∈ (0..^(♯‘𝐹))(𝐼‘(𝐹‘𝑖)) = {(𝑃‘𝑖), (𝑃‘(𝑖 + 1))} → ((𝐺 ∈ USGraph ∧ (♯‘𝐹) = 2) → ∃𝑥 ∈ 𝑉 ∃𝑦 ∈ (𝑉 ∖ {𝑥})∃𝑧 ∈ (𝑉 ∖ {𝑥, 𝑦})(((𝑃‘0) = 𝑥 ∧ (𝑃‘1) = 𝑦 ∧ (𝑃‘2) = 𝑧) ∧ ((𝐼‘(𝐹‘0)) = {𝑥, 𝑦} ∧ (𝐼‘(𝐹‘1)) = {𝑦, 𝑧})))))) | 
| 149 | 148 | 3imp 1110 | 1
⊢ ((𝐹:(0..^(♯‘𝐹))–1-1→dom 𝐼 ∧ 𝑃:(0...(♯‘𝐹))⟶𝑉 ∧ ∀𝑖 ∈ (0..^(♯‘𝐹))(𝐼‘(𝐹‘𝑖)) = {(𝑃‘𝑖), (𝑃‘(𝑖 + 1))}) → ((𝐺 ∈ USGraph ∧ (♯‘𝐹) = 2) → ∃𝑥 ∈ 𝑉 ∃𝑦 ∈ (𝑉 ∖ {𝑥})∃𝑧 ∈ (𝑉 ∖ {𝑥, 𝑦})(((𝑃‘0) = 𝑥 ∧ (𝑃‘1) = 𝑦 ∧ (𝑃‘2) = 𝑧) ∧ ((𝐼‘(𝐹‘0)) = {𝑥, 𝑦} ∧ (𝐼‘(𝐹‘1)) = {𝑦, 𝑧})))) |