Step |
Hyp |
Ref |
Expression |
1 |
|
dfifp2 |
|
2 |
|
dfbi2 |
|
3 |
2
|
imbi2i |
|
4 |
|
jcab |
|
5 |
3 4
|
bitri |
|
6 |
|
dfbi2 |
|
7 |
6
|
imbi2i |
|
8 |
|
jcab |
|
9 |
7 8
|
bitri |
|
10 |
5 9
|
anbi12i |
|
11 |
|
an4 |
|
12 |
10 11
|
bitri |
|
13 |
|
dfifp2 |
|
14 |
|
ifpimimb |
|
15 |
13 14
|
bitr3i |
|
16 |
|
dfifp2 |
|
17 |
|
ifpimimb |
|
18 |
16 17
|
bitr3i |
|
19 |
15 18
|
anbi12i |
|
20 |
|
dfbi2 |
|
21 |
19 20
|
bitr4i |
|
22 |
1 12 21
|
3bitri |
|