Step |
Hyp |
Ref |
Expression |
1 |
|
eldif |
|
2 |
|
velpw |
|
3 |
|
velsn |
|
4 |
3
|
necon3bbii |
|
5 |
2 4
|
anbi12i |
|
6 |
1 5
|
bitri |
|
7 |
|
brdif |
|
8 |
|
epel |
|
9 |
|
vex |
|
10 |
|
vex |
|
11 |
9 10
|
coep |
|
12 |
|
vex |
|
13 |
9 12
|
brcnv |
|
14 |
13
|
rexbii |
|
15 |
|
dfrex2 |
|
16 |
11 14 15
|
3bitrri |
|
17 |
16
|
con1bii |
|
18 |
8 17
|
anbi12i |
|
19 |
7 18
|
bitri |
|
20 |
19
|
exbii |
|
21 |
10
|
elrn |
|
22 |
|
df-rex |
|
23 |
20 21 22
|
3bitr4i |
|
24 |
6 23
|
imbi12i |
|
25 |
24
|
albii |
|
26 |
|
dfss2 |
|
27 |
|
df-fr |
|
28 |
25 26 27
|
3bitr4ri |
|