| Step |
Hyp |
Ref |
Expression |
| 1 |
|
f1of1 |
⊢ ( 𝑓 : ( 0 ..^ 3 ) –1-1-onto→ { 𝑥 , 𝑦 , 𝑧 } → 𝑓 : ( 0 ..^ 3 ) –1-1→ { 𝑥 , 𝑦 , 𝑧 } ) |
| 2 |
|
fvf1tp |
⊢ ( 𝑓 : ( 0 ..^ 3 ) –1-1→ { 𝑥 , 𝑦 , 𝑧 } → ( ( ( ( 𝑓 ‘ 0 ) = 𝑥 ∧ ( 𝑓 ‘ 1 ) = 𝑦 ∧ ( 𝑓 ‘ 2 ) = 𝑧 ) ∨ ( ( 𝑓 ‘ 0 ) = 𝑥 ∧ ( 𝑓 ‘ 1 ) = 𝑧 ∧ ( 𝑓 ‘ 2 ) = 𝑦 ) ) ∨ ( ( ( 𝑓 ‘ 0 ) = 𝑦 ∧ ( 𝑓 ‘ 1 ) = 𝑥 ∧ ( 𝑓 ‘ 2 ) = 𝑧 ) ∨ ( ( 𝑓 ‘ 0 ) = 𝑦 ∧ ( 𝑓 ‘ 1 ) = 𝑧 ∧ ( 𝑓 ‘ 2 ) = 𝑥 ) ) ∨ ( ( ( 𝑓 ‘ 0 ) = 𝑧 ∧ ( 𝑓 ‘ 1 ) = 𝑥 ∧ ( 𝑓 ‘ 2 ) = 𝑦 ) ∨ ( ( 𝑓 ‘ 0 ) = 𝑧 ∧ ( 𝑓 ‘ 1 ) = 𝑦 ∧ ( 𝑓 ‘ 2 ) = 𝑥 ) ) ) ) |
| 3 |
|
simp1 |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑥 ∧ ( 𝑓 ‘ 1 ) = 𝑦 ∧ ( 𝑓 ‘ 2 ) = 𝑧 ) → ( 𝑓 ‘ 0 ) = 𝑥 ) |
| 4 |
|
simp2 |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑥 ∧ ( 𝑓 ‘ 1 ) = 𝑦 ∧ ( 𝑓 ‘ 2 ) = 𝑧 ) → ( 𝑓 ‘ 1 ) = 𝑦 ) |
| 5 |
3 4
|
preq12d |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑥 ∧ ( 𝑓 ‘ 1 ) = 𝑦 ∧ ( 𝑓 ‘ 2 ) = 𝑧 ) → { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 1 ) } = { 𝑥 , 𝑦 } ) |
| 6 |
5
|
eleq1d |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑥 ∧ ( 𝑓 ‘ 1 ) = 𝑦 ∧ ( 𝑓 ‘ 2 ) = 𝑧 ) → ( { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 1 ) } ∈ 𝐸 ↔ { 𝑥 , 𝑦 } ∈ 𝐸 ) ) |
| 7 |
|
simp3 |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑥 ∧ ( 𝑓 ‘ 1 ) = 𝑦 ∧ ( 𝑓 ‘ 2 ) = 𝑧 ) → ( 𝑓 ‘ 2 ) = 𝑧 ) |
| 8 |
3 7
|
preq12d |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑥 ∧ ( 𝑓 ‘ 1 ) = 𝑦 ∧ ( 𝑓 ‘ 2 ) = 𝑧 ) → { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 2 ) } = { 𝑥 , 𝑧 } ) |
| 9 |
8
|
eleq1d |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑥 ∧ ( 𝑓 ‘ 1 ) = 𝑦 ∧ ( 𝑓 ‘ 2 ) = 𝑧 ) → ( { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 2 ) } ∈ 𝐸 ↔ { 𝑥 , 𝑧 } ∈ 𝐸 ) ) |
| 10 |
4 7
|
preq12d |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑥 ∧ ( 𝑓 ‘ 1 ) = 𝑦 ∧ ( 𝑓 ‘ 2 ) = 𝑧 ) → { ( 𝑓 ‘ 1 ) , ( 𝑓 ‘ 2 ) } = { 𝑦 , 𝑧 } ) |
| 11 |
10
|
eleq1d |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑥 ∧ ( 𝑓 ‘ 1 ) = 𝑦 ∧ ( 𝑓 ‘ 2 ) = 𝑧 ) → ( { ( 𝑓 ‘ 1 ) , ( 𝑓 ‘ 2 ) } ∈ 𝐸 ↔ { 𝑦 , 𝑧 } ∈ 𝐸 ) ) |
| 12 |
6 9 11
|
3anbi123d |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑥 ∧ ( 𝑓 ‘ 1 ) = 𝑦 ∧ ( 𝑓 ‘ 2 ) = 𝑧 ) → ( ( { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 1 ) } ∈ 𝐸 ∧ { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 2 ) } ∈ 𝐸 ∧ { ( 𝑓 ‘ 1 ) , ( 𝑓 ‘ 2 ) } ∈ 𝐸 ) ↔ ( { 𝑥 , 𝑦 } ∈ 𝐸 ∧ { 𝑥 , 𝑧 } ∈ 𝐸 ∧ { 𝑦 , 𝑧 } ∈ 𝐸 ) ) ) |
| 13 |
12
|
biimpd |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑥 ∧ ( 𝑓 ‘ 1 ) = 𝑦 ∧ ( 𝑓 ‘ 2 ) = 𝑧 ) → ( ( { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 1 ) } ∈ 𝐸 ∧ { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 2 ) } ∈ 𝐸 ∧ { ( 𝑓 ‘ 1 ) , ( 𝑓 ‘ 2 ) } ∈ 𝐸 ) → ( { 𝑥 , 𝑦 } ∈ 𝐸 ∧ { 𝑥 , 𝑧 } ∈ 𝐸 ∧ { 𝑦 , 𝑧 } ∈ 𝐸 ) ) ) |
| 14 |
|
simp1 |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑥 ∧ ( 𝑓 ‘ 1 ) = 𝑧 ∧ ( 𝑓 ‘ 2 ) = 𝑦 ) → ( 𝑓 ‘ 0 ) = 𝑥 ) |
| 15 |
|
simp2 |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑥 ∧ ( 𝑓 ‘ 1 ) = 𝑧 ∧ ( 𝑓 ‘ 2 ) = 𝑦 ) → ( 𝑓 ‘ 1 ) = 𝑧 ) |
| 16 |
14 15
|
preq12d |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑥 ∧ ( 𝑓 ‘ 1 ) = 𝑧 ∧ ( 𝑓 ‘ 2 ) = 𝑦 ) → { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 1 ) } = { 𝑥 , 𝑧 } ) |
| 17 |
16
|
eleq1d |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑥 ∧ ( 𝑓 ‘ 1 ) = 𝑧 ∧ ( 𝑓 ‘ 2 ) = 𝑦 ) → ( { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 1 ) } ∈ 𝐸 ↔ { 𝑥 , 𝑧 } ∈ 𝐸 ) ) |
| 18 |
|
simp3 |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑥 ∧ ( 𝑓 ‘ 1 ) = 𝑧 ∧ ( 𝑓 ‘ 2 ) = 𝑦 ) → ( 𝑓 ‘ 2 ) = 𝑦 ) |
| 19 |
14 18
|
preq12d |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑥 ∧ ( 𝑓 ‘ 1 ) = 𝑧 ∧ ( 𝑓 ‘ 2 ) = 𝑦 ) → { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 2 ) } = { 𝑥 , 𝑦 } ) |
| 20 |
19
|
eleq1d |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑥 ∧ ( 𝑓 ‘ 1 ) = 𝑧 ∧ ( 𝑓 ‘ 2 ) = 𝑦 ) → ( { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 2 ) } ∈ 𝐸 ↔ { 𝑥 , 𝑦 } ∈ 𝐸 ) ) |
| 21 |
15 18
|
preq12d |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑥 ∧ ( 𝑓 ‘ 1 ) = 𝑧 ∧ ( 𝑓 ‘ 2 ) = 𝑦 ) → { ( 𝑓 ‘ 1 ) , ( 𝑓 ‘ 2 ) } = { 𝑧 , 𝑦 } ) |
| 22 |
21
|
eleq1d |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑥 ∧ ( 𝑓 ‘ 1 ) = 𝑧 ∧ ( 𝑓 ‘ 2 ) = 𝑦 ) → ( { ( 𝑓 ‘ 1 ) , ( 𝑓 ‘ 2 ) } ∈ 𝐸 ↔ { 𝑧 , 𝑦 } ∈ 𝐸 ) ) |
| 23 |
17 20 22
|
3anbi123d |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑥 ∧ ( 𝑓 ‘ 1 ) = 𝑧 ∧ ( 𝑓 ‘ 2 ) = 𝑦 ) → ( ( { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 1 ) } ∈ 𝐸 ∧ { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 2 ) } ∈ 𝐸 ∧ { ( 𝑓 ‘ 1 ) , ( 𝑓 ‘ 2 ) } ∈ 𝐸 ) ↔ ( { 𝑥 , 𝑧 } ∈ 𝐸 ∧ { 𝑥 , 𝑦 } ∈ 𝐸 ∧ { 𝑧 , 𝑦 } ∈ 𝐸 ) ) ) |
| 24 |
|
3ancoma |
⊢ ( ( { 𝑥 , 𝑧 } ∈ 𝐸 ∧ { 𝑥 , 𝑦 } ∈ 𝐸 ∧ { 𝑧 , 𝑦 } ∈ 𝐸 ) ↔ ( { 𝑥 , 𝑦 } ∈ 𝐸 ∧ { 𝑥 , 𝑧 } ∈ 𝐸 ∧ { 𝑧 , 𝑦 } ∈ 𝐸 ) ) |
| 25 |
|
prcom |
⊢ { 𝑧 , 𝑦 } = { 𝑦 , 𝑧 } |
| 26 |
25
|
eleq1i |
⊢ ( { 𝑧 , 𝑦 } ∈ 𝐸 ↔ { 𝑦 , 𝑧 } ∈ 𝐸 ) |
| 27 |
26
|
3anbi3i |
⊢ ( ( { 𝑥 , 𝑦 } ∈ 𝐸 ∧ { 𝑥 , 𝑧 } ∈ 𝐸 ∧ { 𝑧 , 𝑦 } ∈ 𝐸 ) ↔ ( { 𝑥 , 𝑦 } ∈ 𝐸 ∧ { 𝑥 , 𝑧 } ∈ 𝐸 ∧ { 𝑦 , 𝑧 } ∈ 𝐸 ) ) |
| 28 |
24 27
|
sylbb |
⊢ ( ( { 𝑥 , 𝑧 } ∈ 𝐸 ∧ { 𝑥 , 𝑦 } ∈ 𝐸 ∧ { 𝑧 , 𝑦 } ∈ 𝐸 ) → ( { 𝑥 , 𝑦 } ∈ 𝐸 ∧ { 𝑥 , 𝑧 } ∈ 𝐸 ∧ { 𝑦 , 𝑧 } ∈ 𝐸 ) ) |
| 29 |
23 28
|
biimtrdi |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑥 ∧ ( 𝑓 ‘ 1 ) = 𝑧 ∧ ( 𝑓 ‘ 2 ) = 𝑦 ) → ( ( { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 1 ) } ∈ 𝐸 ∧ { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 2 ) } ∈ 𝐸 ∧ { ( 𝑓 ‘ 1 ) , ( 𝑓 ‘ 2 ) } ∈ 𝐸 ) → ( { 𝑥 , 𝑦 } ∈ 𝐸 ∧ { 𝑥 , 𝑧 } ∈ 𝐸 ∧ { 𝑦 , 𝑧 } ∈ 𝐸 ) ) ) |
| 30 |
13 29
|
jaoi |
⊢ ( ( ( ( 𝑓 ‘ 0 ) = 𝑥 ∧ ( 𝑓 ‘ 1 ) = 𝑦 ∧ ( 𝑓 ‘ 2 ) = 𝑧 ) ∨ ( ( 𝑓 ‘ 0 ) = 𝑥 ∧ ( 𝑓 ‘ 1 ) = 𝑧 ∧ ( 𝑓 ‘ 2 ) = 𝑦 ) ) → ( ( { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 1 ) } ∈ 𝐸 ∧ { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 2 ) } ∈ 𝐸 ∧ { ( 𝑓 ‘ 1 ) , ( 𝑓 ‘ 2 ) } ∈ 𝐸 ) → ( { 𝑥 , 𝑦 } ∈ 𝐸 ∧ { 𝑥 , 𝑧 } ∈ 𝐸 ∧ { 𝑦 , 𝑧 } ∈ 𝐸 ) ) ) |
| 31 |
|
simp1 |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑦 ∧ ( 𝑓 ‘ 1 ) = 𝑥 ∧ ( 𝑓 ‘ 2 ) = 𝑧 ) → ( 𝑓 ‘ 0 ) = 𝑦 ) |
| 32 |
|
simp2 |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑦 ∧ ( 𝑓 ‘ 1 ) = 𝑥 ∧ ( 𝑓 ‘ 2 ) = 𝑧 ) → ( 𝑓 ‘ 1 ) = 𝑥 ) |
| 33 |
31 32
|
preq12d |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑦 ∧ ( 𝑓 ‘ 1 ) = 𝑥 ∧ ( 𝑓 ‘ 2 ) = 𝑧 ) → { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 1 ) } = { 𝑦 , 𝑥 } ) |
| 34 |
33
|
eleq1d |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑦 ∧ ( 𝑓 ‘ 1 ) = 𝑥 ∧ ( 𝑓 ‘ 2 ) = 𝑧 ) → ( { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 1 ) } ∈ 𝐸 ↔ { 𝑦 , 𝑥 } ∈ 𝐸 ) ) |
| 35 |
|
simp3 |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑦 ∧ ( 𝑓 ‘ 1 ) = 𝑥 ∧ ( 𝑓 ‘ 2 ) = 𝑧 ) → ( 𝑓 ‘ 2 ) = 𝑧 ) |
| 36 |
31 35
|
preq12d |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑦 ∧ ( 𝑓 ‘ 1 ) = 𝑥 ∧ ( 𝑓 ‘ 2 ) = 𝑧 ) → { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 2 ) } = { 𝑦 , 𝑧 } ) |
| 37 |
36
|
eleq1d |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑦 ∧ ( 𝑓 ‘ 1 ) = 𝑥 ∧ ( 𝑓 ‘ 2 ) = 𝑧 ) → ( { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 2 ) } ∈ 𝐸 ↔ { 𝑦 , 𝑧 } ∈ 𝐸 ) ) |
| 38 |
32 35
|
preq12d |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑦 ∧ ( 𝑓 ‘ 1 ) = 𝑥 ∧ ( 𝑓 ‘ 2 ) = 𝑧 ) → { ( 𝑓 ‘ 1 ) , ( 𝑓 ‘ 2 ) } = { 𝑥 , 𝑧 } ) |
| 39 |
38
|
eleq1d |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑦 ∧ ( 𝑓 ‘ 1 ) = 𝑥 ∧ ( 𝑓 ‘ 2 ) = 𝑧 ) → ( { ( 𝑓 ‘ 1 ) , ( 𝑓 ‘ 2 ) } ∈ 𝐸 ↔ { 𝑥 , 𝑧 } ∈ 𝐸 ) ) |
| 40 |
34 37 39
|
3anbi123d |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑦 ∧ ( 𝑓 ‘ 1 ) = 𝑥 ∧ ( 𝑓 ‘ 2 ) = 𝑧 ) → ( ( { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 1 ) } ∈ 𝐸 ∧ { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 2 ) } ∈ 𝐸 ∧ { ( 𝑓 ‘ 1 ) , ( 𝑓 ‘ 2 ) } ∈ 𝐸 ) ↔ ( { 𝑦 , 𝑥 } ∈ 𝐸 ∧ { 𝑦 , 𝑧 } ∈ 𝐸 ∧ { 𝑥 , 𝑧 } ∈ 𝐸 ) ) ) |
| 41 |
|
3ancomb |
⊢ ( ( { 𝑦 , 𝑥 } ∈ 𝐸 ∧ { 𝑦 , 𝑧 } ∈ 𝐸 ∧ { 𝑥 , 𝑧 } ∈ 𝐸 ) ↔ ( { 𝑦 , 𝑥 } ∈ 𝐸 ∧ { 𝑥 , 𝑧 } ∈ 𝐸 ∧ { 𝑦 , 𝑧 } ∈ 𝐸 ) ) |
| 42 |
|
prcom |
⊢ { 𝑦 , 𝑥 } = { 𝑥 , 𝑦 } |
| 43 |
42
|
eleq1i |
⊢ ( { 𝑦 , 𝑥 } ∈ 𝐸 ↔ { 𝑥 , 𝑦 } ∈ 𝐸 ) |
| 44 |
43
|
3anbi1i |
⊢ ( ( { 𝑦 , 𝑥 } ∈ 𝐸 ∧ { 𝑥 , 𝑧 } ∈ 𝐸 ∧ { 𝑦 , 𝑧 } ∈ 𝐸 ) ↔ ( { 𝑥 , 𝑦 } ∈ 𝐸 ∧ { 𝑥 , 𝑧 } ∈ 𝐸 ∧ { 𝑦 , 𝑧 } ∈ 𝐸 ) ) |
| 45 |
41 44
|
sylbb |
⊢ ( ( { 𝑦 , 𝑥 } ∈ 𝐸 ∧ { 𝑦 , 𝑧 } ∈ 𝐸 ∧ { 𝑥 , 𝑧 } ∈ 𝐸 ) → ( { 𝑥 , 𝑦 } ∈ 𝐸 ∧ { 𝑥 , 𝑧 } ∈ 𝐸 ∧ { 𝑦 , 𝑧 } ∈ 𝐸 ) ) |
| 46 |
40 45
|
biimtrdi |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑦 ∧ ( 𝑓 ‘ 1 ) = 𝑥 ∧ ( 𝑓 ‘ 2 ) = 𝑧 ) → ( ( { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 1 ) } ∈ 𝐸 ∧ { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 2 ) } ∈ 𝐸 ∧ { ( 𝑓 ‘ 1 ) , ( 𝑓 ‘ 2 ) } ∈ 𝐸 ) → ( { 𝑥 , 𝑦 } ∈ 𝐸 ∧ { 𝑥 , 𝑧 } ∈ 𝐸 ∧ { 𝑦 , 𝑧 } ∈ 𝐸 ) ) ) |
| 47 |
|
simp1 |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑦 ∧ ( 𝑓 ‘ 1 ) = 𝑧 ∧ ( 𝑓 ‘ 2 ) = 𝑥 ) → ( 𝑓 ‘ 0 ) = 𝑦 ) |
| 48 |
|
simp2 |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑦 ∧ ( 𝑓 ‘ 1 ) = 𝑧 ∧ ( 𝑓 ‘ 2 ) = 𝑥 ) → ( 𝑓 ‘ 1 ) = 𝑧 ) |
| 49 |
47 48
|
preq12d |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑦 ∧ ( 𝑓 ‘ 1 ) = 𝑧 ∧ ( 𝑓 ‘ 2 ) = 𝑥 ) → { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 1 ) } = { 𝑦 , 𝑧 } ) |
| 50 |
49
|
eleq1d |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑦 ∧ ( 𝑓 ‘ 1 ) = 𝑧 ∧ ( 𝑓 ‘ 2 ) = 𝑥 ) → ( { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 1 ) } ∈ 𝐸 ↔ { 𝑦 , 𝑧 } ∈ 𝐸 ) ) |
| 51 |
|
simp3 |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑦 ∧ ( 𝑓 ‘ 1 ) = 𝑧 ∧ ( 𝑓 ‘ 2 ) = 𝑥 ) → ( 𝑓 ‘ 2 ) = 𝑥 ) |
| 52 |
47 51
|
preq12d |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑦 ∧ ( 𝑓 ‘ 1 ) = 𝑧 ∧ ( 𝑓 ‘ 2 ) = 𝑥 ) → { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 2 ) } = { 𝑦 , 𝑥 } ) |
| 53 |
52
|
eleq1d |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑦 ∧ ( 𝑓 ‘ 1 ) = 𝑧 ∧ ( 𝑓 ‘ 2 ) = 𝑥 ) → ( { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 2 ) } ∈ 𝐸 ↔ { 𝑦 , 𝑥 } ∈ 𝐸 ) ) |
| 54 |
48 51
|
preq12d |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑦 ∧ ( 𝑓 ‘ 1 ) = 𝑧 ∧ ( 𝑓 ‘ 2 ) = 𝑥 ) → { ( 𝑓 ‘ 1 ) , ( 𝑓 ‘ 2 ) } = { 𝑧 , 𝑥 } ) |
| 55 |
54
|
eleq1d |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑦 ∧ ( 𝑓 ‘ 1 ) = 𝑧 ∧ ( 𝑓 ‘ 2 ) = 𝑥 ) → ( { ( 𝑓 ‘ 1 ) , ( 𝑓 ‘ 2 ) } ∈ 𝐸 ↔ { 𝑧 , 𝑥 } ∈ 𝐸 ) ) |
| 56 |
50 53 55
|
3anbi123d |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑦 ∧ ( 𝑓 ‘ 1 ) = 𝑧 ∧ ( 𝑓 ‘ 2 ) = 𝑥 ) → ( ( { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 1 ) } ∈ 𝐸 ∧ { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 2 ) } ∈ 𝐸 ∧ { ( 𝑓 ‘ 1 ) , ( 𝑓 ‘ 2 ) } ∈ 𝐸 ) ↔ ( { 𝑦 , 𝑧 } ∈ 𝐸 ∧ { 𝑦 , 𝑥 } ∈ 𝐸 ∧ { 𝑧 , 𝑥 } ∈ 𝐸 ) ) ) |
| 57 |
|
3anrot |
⊢ ( ( { 𝑦 , 𝑧 } ∈ 𝐸 ∧ { 𝑦 , 𝑥 } ∈ 𝐸 ∧ { 𝑧 , 𝑥 } ∈ 𝐸 ) ↔ ( { 𝑦 , 𝑥 } ∈ 𝐸 ∧ { 𝑧 , 𝑥 } ∈ 𝐸 ∧ { 𝑦 , 𝑧 } ∈ 𝐸 ) ) |
| 58 |
|
prcom |
⊢ { 𝑧 , 𝑥 } = { 𝑥 , 𝑧 } |
| 59 |
58
|
eleq1i |
⊢ ( { 𝑧 , 𝑥 } ∈ 𝐸 ↔ { 𝑥 , 𝑧 } ∈ 𝐸 ) |
| 60 |
|
biid |
⊢ ( { 𝑦 , 𝑧 } ∈ 𝐸 ↔ { 𝑦 , 𝑧 } ∈ 𝐸 ) |
| 61 |
43 59 60
|
3anbi123i |
⊢ ( ( { 𝑦 , 𝑥 } ∈ 𝐸 ∧ { 𝑧 , 𝑥 } ∈ 𝐸 ∧ { 𝑦 , 𝑧 } ∈ 𝐸 ) ↔ ( { 𝑥 , 𝑦 } ∈ 𝐸 ∧ { 𝑥 , 𝑧 } ∈ 𝐸 ∧ { 𝑦 , 𝑧 } ∈ 𝐸 ) ) |
| 62 |
57 61
|
sylbb |
⊢ ( ( { 𝑦 , 𝑧 } ∈ 𝐸 ∧ { 𝑦 , 𝑥 } ∈ 𝐸 ∧ { 𝑧 , 𝑥 } ∈ 𝐸 ) → ( { 𝑥 , 𝑦 } ∈ 𝐸 ∧ { 𝑥 , 𝑧 } ∈ 𝐸 ∧ { 𝑦 , 𝑧 } ∈ 𝐸 ) ) |
| 63 |
56 62
|
biimtrdi |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑦 ∧ ( 𝑓 ‘ 1 ) = 𝑧 ∧ ( 𝑓 ‘ 2 ) = 𝑥 ) → ( ( { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 1 ) } ∈ 𝐸 ∧ { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 2 ) } ∈ 𝐸 ∧ { ( 𝑓 ‘ 1 ) , ( 𝑓 ‘ 2 ) } ∈ 𝐸 ) → ( { 𝑥 , 𝑦 } ∈ 𝐸 ∧ { 𝑥 , 𝑧 } ∈ 𝐸 ∧ { 𝑦 , 𝑧 } ∈ 𝐸 ) ) ) |
| 64 |
46 63
|
jaoi |
⊢ ( ( ( ( 𝑓 ‘ 0 ) = 𝑦 ∧ ( 𝑓 ‘ 1 ) = 𝑥 ∧ ( 𝑓 ‘ 2 ) = 𝑧 ) ∨ ( ( 𝑓 ‘ 0 ) = 𝑦 ∧ ( 𝑓 ‘ 1 ) = 𝑧 ∧ ( 𝑓 ‘ 2 ) = 𝑥 ) ) → ( ( { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 1 ) } ∈ 𝐸 ∧ { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 2 ) } ∈ 𝐸 ∧ { ( 𝑓 ‘ 1 ) , ( 𝑓 ‘ 2 ) } ∈ 𝐸 ) → ( { 𝑥 , 𝑦 } ∈ 𝐸 ∧ { 𝑥 , 𝑧 } ∈ 𝐸 ∧ { 𝑦 , 𝑧 } ∈ 𝐸 ) ) ) |
| 65 |
|
simp1 |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑧 ∧ ( 𝑓 ‘ 1 ) = 𝑥 ∧ ( 𝑓 ‘ 2 ) = 𝑦 ) → ( 𝑓 ‘ 0 ) = 𝑧 ) |
| 66 |
|
simp2 |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑧 ∧ ( 𝑓 ‘ 1 ) = 𝑥 ∧ ( 𝑓 ‘ 2 ) = 𝑦 ) → ( 𝑓 ‘ 1 ) = 𝑥 ) |
| 67 |
65 66
|
preq12d |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑧 ∧ ( 𝑓 ‘ 1 ) = 𝑥 ∧ ( 𝑓 ‘ 2 ) = 𝑦 ) → { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 1 ) } = { 𝑧 , 𝑥 } ) |
| 68 |
67
|
eleq1d |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑧 ∧ ( 𝑓 ‘ 1 ) = 𝑥 ∧ ( 𝑓 ‘ 2 ) = 𝑦 ) → ( { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 1 ) } ∈ 𝐸 ↔ { 𝑧 , 𝑥 } ∈ 𝐸 ) ) |
| 69 |
|
simp3 |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑧 ∧ ( 𝑓 ‘ 1 ) = 𝑥 ∧ ( 𝑓 ‘ 2 ) = 𝑦 ) → ( 𝑓 ‘ 2 ) = 𝑦 ) |
| 70 |
65 69
|
preq12d |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑧 ∧ ( 𝑓 ‘ 1 ) = 𝑥 ∧ ( 𝑓 ‘ 2 ) = 𝑦 ) → { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 2 ) } = { 𝑧 , 𝑦 } ) |
| 71 |
70
|
eleq1d |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑧 ∧ ( 𝑓 ‘ 1 ) = 𝑥 ∧ ( 𝑓 ‘ 2 ) = 𝑦 ) → ( { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 2 ) } ∈ 𝐸 ↔ { 𝑧 , 𝑦 } ∈ 𝐸 ) ) |
| 72 |
66 69
|
preq12d |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑧 ∧ ( 𝑓 ‘ 1 ) = 𝑥 ∧ ( 𝑓 ‘ 2 ) = 𝑦 ) → { ( 𝑓 ‘ 1 ) , ( 𝑓 ‘ 2 ) } = { 𝑥 , 𝑦 } ) |
| 73 |
72
|
eleq1d |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑧 ∧ ( 𝑓 ‘ 1 ) = 𝑥 ∧ ( 𝑓 ‘ 2 ) = 𝑦 ) → ( { ( 𝑓 ‘ 1 ) , ( 𝑓 ‘ 2 ) } ∈ 𝐸 ↔ { 𝑥 , 𝑦 } ∈ 𝐸 ) ) |
| 74 |
68 71 73
|
3anbi123d |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑧 ∧ ( 𝑓 ‘ 1 ) = 𝑥 ∧ ( 𝑓 ‘ 2 ) = 𝑦 ) → ( ( { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 1 ) } ∈ 𝐸 ∧ { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 2 ) } ∈ 𝐸 ∧ { ( 𝑓 ‘ 1 ) , ( 𝑓 ‘ 2 ) } ∈ 𝐸 ) ↔ ( { 𝑧 , 𝑥 } ∈ 𝐸 ∧ { 𝑧 , 𝑦 } ∈ 𝐸 ∧ { 𝑥 , 𝑦 } ∈ 𝐸 ) ) ) |
| 75 |
|
3anrot |
⊢ ( ( { 𝑥 , 𝑦 } ∈ 𝐸 ∧ { 𝑥 , 𝑧 } ∈ 𝐸 ∧ { 𝑦 , 𝑧 } ∈ 𝐸 ) ↔ ( { 𝑥 , 𝑧 } ∈ 𝐸 ∧ { 𝑦 , 𝑧 } ∈ 𝐸 ∧ { 𝑥 , 𝑦 } ∈ 𝐸 ) ) |
| 76 |
|
prcom |
⊢ { 𝑥 , 𝑧 } = { 𝑧 , 𝑥 } |
| 77 |
76
|
eleq1i |
⊢ ( { 𝑥 , 𝑧 } ∈ 𝐸 ↔ { 𝑧 , 𝑥 } ∈ 𝐸 ) |
| 78 |
|
prcom |
⊢ { 𝑦 , 𝑧 } = { 𝑧 , 𝑦 } |
| 79 |
78
|
eleq1i |
⊢ ( { 𝑦 , 𝑧 } ∈ 𝐸 ↔ { 𝑧 , 𝑦 } ∈ 𝐸 ) |
| 80 |
|
biid |
⊢ ( { 𝑥 , 𝑦 } ∈ 𝐸 ↔ { 𝑥 , 𝑦 } ∈ 𝐸 ) |
| 81 |
77 79 80
|
3anbi123i |
⊢ ( ( { 𝑥 , 𝑧 } ∈ 𝐸 ∧ { 𝑦 , 𝑧 } ∈ 𝐸 ∧ { 𝑥 , 𝑦 } ∈ 𝐸 ) ↔ ( { 𝑧 , 𝑥 } ∈ 𝐸 ∧ { 𝑧 , 𝑦 } ∈ 𝐸 ∧ { 𝑥 , 𝑦 } ∈ 𝐸 ) ) |
| 82 |
75 81
|
sylbbr |
⊢ ( ( { 𝑧 , 𝑥 } ∈ 𝐸 ∧ { 𝑧 , 𝑦 } ∈ 𝐸 ∧ { 𝑥 , 𝑦 } ∈ 𝐸 ) → ( { 𝑥 , 𝑦 } ∈ 𝐸 ∧ { 𝑥 , 𝑧 } ∈ 𝐸 ∧ { 𝑦 , 𝑧 } ∈ 𝐸 ) ) |
| 83 |
74 82
|
biimtrdi |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑧 ∧ ( 𝑓 ‘ 1 ) = 𝑥 ∧ ( 𝑓 ‘ 2 ) = 𝑦 ) → ( ( { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 1 ) } ∈ 𝐸 ∧ { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 2 ) } ∈ 𝐸 ∧ { ( 𝑓 ‘ 1 ) , ( 𝑓 ‘ 2 ) } ∈ 𝐸 ) → ( { 𝑥 , 𝑦 } ∈ 𝐸 ∧ { 𝑥 , 𝑧 } ∈ 𝐸 ∧ { 𝑦 , 𝑧 } ∈ 𝐸 ) ) ) |
| 84 |
|
simp1 |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑧 ∧ ( 𝑓 ‘ 1 ) = 𝑦 ∧ ( 𝑓 ‘ 2 ) = 𝑥 ) → ( 𝑓 ‘ 0 ) = 𝑧 ) |
| 85 |
|
simp2 |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑧 ∧ ( 𝑓 ‘ 1 ) = 𝑦 ∧ ( 𝑓 ‘ 2 ) = 𝑥 ) → ( 𝑓 ‘ 1 ) = 𝑦 ) |
| 86 |
84 85
|
preq12d |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑧 ∧ ( 𝑓 ‘ 1 ) = 𝑦 ∧ ( 𝑓 ‘ 2 ) = 𝑥 ) → { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 1 ) } = { 𝑧 , 𝑦 } ) |
| 87 |
86
|
eleq1d |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑧 ∧ ( 𝑓 ‘ 1 ) = 𝑦 ∧ ( 𝑓 ‘ 2 ) = 𝑥 ) → ( { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 1 ) } ∈ 𝐸 ↔ { 𝑧 , 𝑦 } ∈ 𝐸 ) ) |
| 88 |
|
simp3 |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑧 ∧ ( 𝑓 ‘ 1 ) = 𝑦 ∧ ( 𝑓 ‘ 2 ) = 𝑥 ) → ( 𝑓 ‘ 2 ) = 𝑥 ) |
| 89 |
84 88
|
preq12d |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑧 ∧ ( 𝑓 ‘ 1 ) = 𝑦 ∧ ( 𝑓 ‘ 2 ) = 𝑥 ) → { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 2 ) } = { 𝑧 , 𝑥 } ) |
| 90 |
89
|
eleq1d |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑧 ∧ ( 𝑓 ‘ 1 ) = 𝑦 ∧ ( 𝑓 ‘ 2 ) = 𝑥 ) → ( { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 2 ) } ∈ 𝐸 ↔ { 𝑧 , 𝑥 } ∈ 𝐸 ) ) |
| 91 |
85 88
|
preq12d |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑧 ∧ ( 𝑓 ‘ 1 ) = 𝑦 ∧ ( 𝑓 ‘ 2 ) = 𝑥 ) → { ( 𝑓 ‘ 1 ) , ( 𝑓 ‘ 2 ) } = { 𝑦 , 𝑥 } ) |
| 92 |
91
|
eleq1d |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑧 ∧ ( 𝑓 ‘ 1 ) = 𝑦 ∧ ( 𝑓 ‘ 2 ) = 𝑥 ) → ( { ( 𝑓 ‘ 1 ) , ( 𝑓 ‘ 2 ) } ∈ 𝐸 ↔ { 𝑦 , 𝑥 } ∈ 𝐸 ) ) |
| 93 |
87 90 92
|
3anbi123d |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑧 ∧ ( 𝑓 ‘ 1 ) = 𝑦 ∧ ( 𝑓 ‘ 2 ) = 𝑥 ) → ( ( { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 1 ) } ∈ 𝐸 ∧ { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 2 ) } ∈ 𝐸 ∧ { ( 𝑓 ‘ 1 ) , ( 𝑓 ‘ 2 ) } ∈ 𝐸 ) ↔ ( { 𝑧 , 𝑦 } ∈ 𝐸 ∧ { 𝑧 , 𝑥 } ∈ 𝐸 ∧ { 𝑦 , 𝑥 } ∈ 𝐸 ) ) ) |
| 94 |
|
3anrev |
⊢ ( ( { 𝑧 , 𝑦 } ∈ 𝐸 ∧ { 𝑧 , 𝑥 } ∈ 𝐸 ∧ { 𝑦 , 𝑥 } ∈ 𝐸 ) ↔ ( { 𝑦 , 𝑥 } ∈ 𝐸 ∧ { 𝑧 , 𝑥 } ∈ 𝐸 ∧ { 𝑧 , 𝑦 } ∈ 𝐸 ) ) |
| 95 |
43 59 26
|
3anbi123i |
⊢ ( ( { 𝑦 , 𝑥 } ∈ 𝐸 ∧ { 𝑧 , 𝑥 } ∈ 𝐸 ∧ { 𝑧 , 𝑦 } ∈ 𝐸 ) ↔ ( { 𝑥 , 𝑦 } ∈ 𝐸 ∧ { 𝑥 , 𝑧 } ∈ 𝐸 ∧ { 𝑦 , 𝑧 } ∈ 𝐸 ) ) |
| 96 |
94 95
|
sylbb |
⊢ ( ( { 𝑧 , 𝑦 } ∈ 𝐸 ∧ { 𝑧 , 𝑥 } ∈ 𝐸 ∧ { 𝑦 , 𝑥 } ∈ 𝐸 ) → ( { 𝑥 , 𝑦 } ∈ 𝐸 ∧ { 𝑥 , 𝑧 } ∈ 𝐸 ∧ { 𝑦 , 𝑧 } ∈ 𝐸 ) ) |
| 97 |
93 96
|
biimtrdi |
⊢ ( ( ( 𝑓 ‘ 0 ) = 𝑧 ∧ ( 𝑓 ‘ 1 ) = 𝑦 ∧ ( 𝑓 ‘ 2 ) = 𝑥 ) → ( ( { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 1 ) } ∈ 𝐸 ∧ { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 2 ) } ∈ 𝐸 ∧ { ( 𝑓 ‘ 1 ) , ( 𝑓 ‘ 2 ) } ∈ 𝐸 ) → ( { 𝑥 , 𝑦 } ∈ 𝐸 ∧ { 𝑥 , 𝑧 } ∈ 𝐸 ∧ { 𝑦 , 𝑧 } ∈ 𝐸 ) ) ) |
| 98 |
83 97
|
jaoi |
⊢ ( ( ( ( 𝑓 ‘ 0 ) = 𝑧 ∧ ( 𝑓 ‘ 1 ) = 𝑥 ∧ ( 𝑓 ‘ 2 ) = 𝑦 ) ∨ ( ( 𝑓 ‘ 0 ) = 𝑧 ∧ ( 𝑓 ‘ 1 ) = 𝑦 ∧ ( 𝑓 ‘ 2 ) = 𝑥 ) ) → ( ( { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 1 ) } ∈ 𝐸 ∧ { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 2 ) } ∈ 𝐸 ∧ { ( 𝑓 ‘ 1 ) , ( 𝑓 ‘ 2 ) } ∈ 𝐸 ) → ( { 𝑥 , 𝑦 } ∈ 𝐸 ∧ { 𝑥 , 𝑧 } ∈ 𝐸 ∧ { 𝑦 , 𝑧 } ∈ 𝐸 ) ) ) |
| 99 |
30 64 98
|
3jaoi |
⊢ ( ( ( ( ( 𝑓 ‘ 0 ) = 𝑥 ∧ ( 𝑓 ‘ 1 ) = 𝑦 ∧ ( 𝑓 ‘ 2 ) = 𝑧 ) ∨ ( ( 𝑓 ‘ 0 ) = 𝑥 ∧ ( 𝑓 ‘ 1 ) = 𝑧 ∧ ( 𝑓 ‘ 2 ) = 𝑦 ) ) ∨ ( ( ( 𝑓 ‘ 0 ) = 𝑦 ∧ ( 𝑓 ‘ 1 ) = 𝑥 ∧ ( 𝑓 ‘ 2 ) = 𝑧 ) ∨ ( ( 𝑓 ‘ 0 ) = 𝑦 ∧ ( 𝑓 ‘ 1 ) = 𝑧 ∧ ( 𝑓 ‘ 2 ) = 𝑥 ) ) ∨ ( ( ( 𝑓 ‘ 0 ) = 𝑧 ∧ ( 𝑓 ‘ 1 ) = 𝑥 ∧ ( 𝑓 ‘ 2 ) = 𝑦 ) ∨ ( ( 𝑓 ‘ 0 ) = 𝑧 ∧ ( 𝑓 ‘ 1 ) = 𝑦 ∧ ( 𝑓 ‘ 2 ) = 𝑥 ) ) ) → ( ( { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 1 ) } ∈ 𝐸 ∧ { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 2 ) } ∈ 𝐸 ∧ { ( 𝑓 ‘ 1 ) , ( 𝑓 ‘ 2 ) } ∈ 𝐸 ) → ( { 𝑥 , 𝑦 } ∈ 𝐸 ∧ { 𝑥 , 𝑧 } ∈ 𝐸 ∧ { 𝑦 , 𝑧 } ∈ 𝐸 ) ) ) |
| 100 |
1 2 99
|
3syl |
⊢ ( 𝑓 : ( 0 ..^ 3 ) –1-1-onto→ { 𝑥 , 𝑦 , 𝑧 } → ( ( { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 1 ) } ∈ 𝐸 ∧ { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 2 ) } ∈ 𝐸 ∧ { ( 𝑓 ‘ 1 ) , ( 𝑓 ‘ 2 ) } ∈ 𝐸 ) → ( { 𝑥 , 𝑦 } ∈ 𝐸 ∧ { 𝑥 , 𝑧 } ∈ 𝐸 ∧ { 𝑦 , 𝑧 } ∈ 𝐸 ) ) ) |
| 101 |
100
|
imp |
⊢ ( ( 𝑓 : ( 0 ..^ 3 ) –1-1-onto→ { 𝑥 , 𝑦 , 𝑧 } ∧ ( { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 1 ) } ∈ 𝐸 ∧ { ( 𝑓 ‘ 0 ) , ( 𝑓 ‘ 2 ) } ∈ 𝐸 ∧ { ( 𝑓 ‘ 1 ) , ( 𝑓 ‘ 2 ) } ∈ 𝐸 ) ) → ( { 𝑥 , 𝑦 } ∈ 𝐸 ∧ { 𝑥 , 𝑧 } ∈ 𝐸 ∧ { 𝑦 , 𝑧 } ∈ 𝐸 ) ) |