| Step |
Hyp |
Ref |
Expression |
| 1 |
|
3anass |
|
| 2 |
|
3anan12 |
|
| 3 |
|
3anrev |
|
| 4 |
|
3anass |
|
| 5 |
3 4
|
bitri |
|
| 6 |
1 2 5
|
3anbi123i |
|
| 7 |
|
3an6 |
|
| 8 |
|
anass |
|
| 9 |
8
|
anbi2i |
|
| 10 |
|
an42 |
|
| 11 |
9 10
|
bitri |
|
| 12 |
|
anass |
|
| 13 |
|
anass |
|
| 14 |
11 12 13
|
3bitr4i |
|
| 15 |
14
|
anbi1i |
|
| 16 |
|
anass |
|
| 17 |
|
anass |
|
| 18 |
15 16 17
|
3bitr3i |
|
| 19 |
|
df-3an |
|
| 20 |
|
df-3an |
|
| 21 |
18 19 20
|
3bitr4i |
|
| 22 |
21
|
anbi2i |
|
| 23 |
6 7 22
|
3bitri |
|