Step |
Hyp |
Ref |
Expression |
1 |
|
nnsgrp.m |
|
2 |
|
nnsscn |
|
3 |
1
|
cnfldsrngbas |
|
4 |
2 3
|
ax-mp |
|
5 |
|
nnex |
|
6 |
1
|
cnfldsrngadd |
|
7 |
5 6
|
ax-mp |
|
8 |
4 7
|
isnmnd |
|
9 |
|
1nn |
|
10 |
9
|
a1i |
|
11 |
|
oveq2 |
|
12 |
|
id |
|
13 |
11 12
|
neeq12d |
|
14 |
13
|
adantl |
|
15 |
|
nnne0 |
|
16 |
15
|
necomd |
|
17 |
|
1cnd |
|
18 |
|
nncn |
|
19 |
17 17 18
|
subadd2d |
|
20 |
|
1m1e0 |
|
21 |
20
|
a1i |
|
22 |
21
|
eqeq1d |
|
23 |
19 22
|
bitr3d |
|
24 |
23
|
necon3bid |
|
25 |
16 24
|
mpbird |
|
26 |
10 14 25
|
rspcedvd |
|
27 |
8 26
|
mprg |
|