n | a(n) |
---|---|
0 | 1 |
1 | -3 |
2 | 0 |
3 | -1 |
4 | -3 |
5 | -9 |
6 | -28 |
7 | -90 |
8 | -297 |
9 | -1001 |
10 | -3432 |
11 | -11934 |
12 | -41990 |
13 | -149226 |
14 | -534888 |
15 | -1931540 |
16 | -7020405 |
17 | -25662825 |
18 | -94287120 |
19 | -347993910 |
20 | -1289624490 |
21 | -4796857230 |
22 | -17902146600 |
23 | -67016296620 |
24 | -251577050010 |
25 | -946844533674 |
26 | -3572042254128 |
27 | -13505406670700 |
[1,-3,0,-1,-3,-9,-28,-90,-297,-1001,-3432,-11934, -41990,-149226,-534888,-1931540,-7020405, -25662825,-94287120,-347993910,-1289624490, -4796857230,-17902146600,-67016296620, -251577050010,-946844533674,-3572042254128, -13505406670700] |