Step |
Hyp |
Ref |
Expression |
1 |
|
fallfacval |
|
2 |
|
1zzd |
|
3 |
|
0zd |
|
4 |
|
nn0z |
|
5 |
|
peano2zm |
|
6 |
4 5
|
syl |
|
7 |
6
|
adantl |
|
8 |
|
simpl |
|
9 |
|
elfznn0 |
|
10 |
9
|
nn0cnd |
|
11 |
|
subcl |
|
12 |
8 10 11
|
syl2an |
|
13 |
|
oveq2 |
|
14 |
2 3 7 12 13
|
fprodshft |
|
15 |
|
0p1e1 |
|
16 |
15
|
a1i |
|
17 |
|
nn0cn |
|
18 |
|
1cnd |
|
19 |
17 18
|
npcand |
|
20 |
19
|
adantl |
|
21 |
16 20
|
oveq12d |
|
22 |
21
|
prodeq1d |
|
23 |
1 14 22
|
3eqtrd |
|