The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | -2 |
| 2 | 0 |
| 3 | 4 |
| 4 | 32 |
| 5 | 48 |
| 6 | -608 |
| 7 | -6400 |
| 8 | -24064 |
| 9 | 163072 |
| 10 | 3567104 |
| 11 | 28394496 |
| 12 | 6535168 |
| 13 | -3250745344 |
| 14 | -50725740544 |
| 15 | -344530853888 |
| 16 | 2476610551808 |
| 17 | 110057610608640 |
| 18 | 1655672654135296 |
| 19 | 9616664975114240 |
| 20 | -195178079811272704 |
| 21 | -6998474114188967936 |
| 22 | -110894925369151848448 |
[1,-2,0,4,32,48,-608,-6400,-24064,163072,3567104, 28394496,6535168,-3250745344,-50725740544, -344530853888,2476610551808,110057610608640, 1655672654135296,9616664975114240, -195178079811272704,-6998474114188967936, -110894925369151848448] |