Step |
Hyp |
Ref |
Expression |
1 |
|
f1f |
|
2 |
1
|
frnd |
|
3 |
|
f1f |
|
4 |
3
|
frnd |
|
5 |
|
unss12 |
|
6 |
2 4 5
|
syl2an |
|
7 |
|
f1f1orn |
|
8 |
|
f1f1orn |
|
9 |
7 8
|
anim12i |
|
10 |
|
simprl |
|
11 |
|
ss2in |
|
12 |
2 4 11
|
syl2an |
|
13 |
|
sseq0 |
|
14 |
12 13
|
sylan |
|
15 |
14
|
adantrl |
|
16 |
10 15
|
jca |
|
17 |
|
f1oun |
|
18 |
9 16 17
|
syl2an2r |
|
19 |
|
f1of1 |
|
20 |
18 19
|
syl |
|
21 |
|
f1ss |
|
22 |
21
|
ancoms |
|
23 |
6 20 22
|
syl2an2r |
|