Step |
Hyp |
Ref |
Expression |
1 |
|
idn1 |
|
2 |
|
sbcor |
|
3 |
2
|
a1i |
|
4 |
1 3
|
e1a |
|
5 |
|
df-3or |
|
6 |
5
|
bicomi |
|
7 |
6
|
ax-gen |
|
8 |
|
spsbc |
|
9 |
1 7 8
|
e10 |
|
10 |
|
sbcbig |
|
11 |
10
|
biimpd |
|
12 |
1 9 11
|
e11 |
|
13 |
|
bitr3 |
|
14 |
13
|
com12 |
|
15 |
4 12 14
|
e11 |
|
16 |
|
sbcor |
|
17 |
16
|
a1i |
|
18 |
1 17
|
e1a |
|
19 |
|
orbi1 |
|
20 |
18 19
|
e1a |
|
21 |
|
bibi1 |
|
22 |
21
|
biimprd |
|
23 |
15 20 22
|
e11 |
|
24 |
|
df-3or |
|
25 |
24
|
bicomi |
|
26 |
|
bibi1 |
|
27 |
26
|
biimprd |
|
28 |
23 25 27
|
e10 |
|
29 |
28
|
in1 |
|