n | a(n) |
---|---|
0 | 1 |
1 | -2 |
2 | -4 |
3 | 40 |
4 | 80 |
5 | -1952 |
6 | -3904 |
7 | 177280 |
8 | 354560 |
9 | -25866752 |
10 | -51733504 |
11 | 5535262720 |
12 | 11070525440 |
13 | -1633165156352 |
14 | -3266330312704 |
15 | 635421069967360 |
16 | 1270842139934720 |
17 | -315212388819402752 |
18 | -630424777638805504 |
19 | 194181169538675507200 |
[1,-2,-4,40,80,-1952,-3904,177280,354560, -25866752,-51733504,5535262720,11070525440, -1633165156352,-3266330312704,635421069967360, 1270842139934720,-315212388819402752, -630424777638805504,194181169538675507200] |