Step |
Hyp |
Ref |
Expression |
1 |
|
axacnd |
|
2 |
|
df-an |
|
3 |
2
|
albii |
|
4 |
|
anass |
|
5 |
|
annim |
|
6 |
|
pm4.63 |
|
7 |
6
|
anbi2i |
|
8 |
5 7
|
bitr3i |
|
9 |
8
|
anbi2i |
|
10 |
|
annim |
|
11 |
4 9 10
|
3bitr2i |
|
12 |
11
|
exbii |
|
13 |
|
exnal |
|
14 |
12 13
|
bitri |
|
15 |
14
|
bibi1i |
|
16 |
|
dfbi1 |
|
17 |
15 16
|
bitri |
|
18 |
17
|
albii |
|
19 |
18
|
exbii |
|
20 |
|
df-ex |
|
21 |
19 20
|
bitri |
|
22 |
3 21
|
imbi12i |
|
23 |
22
|
2albii |
|
24 |
23
|
exbii |
|
25 |
|
df-ex |
|
26 |
24 25
|
bitri |
|
27 |
1 26
|
mpbi |
|