n | a(n) |
---|---|
0 | 1 |
1 | 1 |
2 | -1 |
3 | 3 |
4 | -15 |
5 | 105 |
6 | -945 |
7 | 10395 |
8 | -135135 |
9 | 2027025 |
10 | -34459425 |
11 | 654729075 |
12 | -13749310575 |
13 | 316234143225 |
14 | -7905853580625 |
15 | 213458046676875 |
16 | -6190283353629375 |
17 | 191898783962510625 |
18 | -6332659870762850625 |
19 | 221643095476699771875 |
20 | -8200794532637891559375 |
21 | 319830986772877770815625 |
[1,1,-1,3,-15,105,-945,10395,-135135,2027025, -34459425,654729075,-13749310575,316234143225, -7905853580625,213458046676875,-6190283353629375, 191898783962510625,-6332659870762850625, 221643095476699771875,-8200794532637891559375, 319830986772877770815625] |