Step |
Hyp |
Ref |
Expression |
1 |
|
supeq123d.a |
|
2 |
|
supeq123d.b |
|
3 |
|
supeq123d.c |
|
4 |
3
|
breqd |
|
5 |
4
|
notbid |
|
6 |
1 5
|
raleqbidv |
|
7 |
3
|
breqd |
|
8 |
3
|
breqd |
|
9 |
1 8
|
rexeqbidv |
|
10 |
7 9
|
imbi12d |
|
11 |
2 10
|
raleqbidv |
|
12 |
6 11
|
anbi12d |
|
13 |
2 12
|
rabeqbidv |
|
14 |
13
|
unieqd |
|
15 |
|
df-sup |
|
16 |
|
df-sup |
|
17 |
14 15 16
|
3eqtr4g |
|