| Step |
Hyp |
Ref |
Expression |
| 1 |
|
4at.l |
|
| 2 |
|
4at.j |
|
| 3 |
|
4at.a |
|
| 4 |
|
simprr |
|
| 5 |
|
simprl |
|
| 6 |
|
simpl1 |
|
| 7 |
|
simpl21 |
|
| 8 |
|
simpl23 |
|
| 9 |
|
simpl31 |
|
| 10 |
|
simpl32 |
|
| 11 |
1 2 3
|
4atlem10a |
|
| 12 |
6 7 8 9 10 11
|
syl131anc |
|
| 13 |
5 12
|
mpbid |
|
| 14 |
4 13
|
breqtrrd |
|
| 15 |
|
simpl22 |
|
| 16 |
|
simpl33 |
|
| 17 |
1 2 3
|
4atlem9 |
|
| 18 |
6 7 15 9 16 17
|
syl131anc |
|
| 19 |
14 18
|
mpbid |
|
| 20 |
19 13
|
eqtrd |
|