Step |
Hyp |
Ref |
Expression |
1 |
|
sbcor |
|
2 |
1
|
a1i |
|
3 |
|
df-3or |
|
4 |
3
|
bicomi |
|
5 |
4
|
sbcbii |
|
6 |
5
|
a1i |
|
7 |
|
sbcor |
|
8 |
7
|
a1i |
|
9 |
8
|
orbi1d |
|
10 |
2 6 9
|
3bitr3d |
|
11 |
|
df-3or |
|
12 |
10 11
|
bitr4di |
|
13 |
12
|
dfvd1ir |
|
14 |
|
sbcel2gv |
|
15 |
14
|
dfvd1ir |
|
16 |
|
sbcel1v |
|
17 |
|
eqsbc2 |
|
18 |
17
|
dfvd1ir |
|
19 |
|
3orbi123 |
|
20 |
19
|
3impexpbicomi |
|
21 |
15 16 18 20
|
e101 |
|
22 |
|
biantr |
|
23 |
13 21 22
|
e11an |
|
24 |
23
|
in1 |
|