Step |
Hyp |
Ref |
Expression |
1 |
|
ntrnei.o |
|
2 |
|
ntrnei.f |
|
3 |
|
ntrnei.r |
|
4 |
1 2 3
|
ntrneif1o |
|
5 |
1 2 3
|
ntrneinex |
|
6 |
|
dff1o3 |
|
7 |
6
|
simprbi |
|
8 |
7
|
adantr |
|
9 |
|
df-rn |
|
10 |
|
f1ofo |
|
11 |
|
forn |
|
12 |
10 11
|
syl |
|
13 |
9 12
|
eqtr3id |
|
14 |
13
|
eleq2d |
|
15 |
14
|
biimpar |
|
16 |
8 15
|
jca |
|
17 |
4 5 16
|
syl2anc |
|
18 |
|
funbrfvb |
|
19 |
17 18
|
syl |
|
20 |
1 2 3
|
ntrneiiex |
|
21 |
|
brcnvg |
|
22 |
5 20 21
|
syl2anc |
|
23 |
19 22
|
bitrd |
|
24 |
3 23
|
mpbird |
|