Step |
Hyp |
Ref |
Expression |
1 |
|
fseq1m1p1.1 |
|
2 |
|
nnm1nn0 |
|
3 |
|
eqid |
|
4 |
3
|
fseq1p1m1 |
|
5 |
2 4
|
syl |
|
6 |
|
nncn |
|
7 |
|
ax-1cn |
|
8 |
|
npcan |
|
9 |
6 7 8
|
sylancl |
|
10 |
9
|
opeq1d |
|
11 |
10
|
sneqd |
|
12 |
11 1
|
eqtr4di |
|
13 |
12
|
uneq2d |
|
14 |
13
|
eqeq2d |
|
15 |
14
|
3anbi3d |
|
16 |
9
|
oveq2d |
|
17 |
16
|
feq2d |
|
18 |
9
|
fveqeq2d |
|
19 |
17 18
|
3anbi12d |
|
20 |
5 15 19
|
3bitr3d |
|