The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | -3 |
| 3 | 9 |
| 4 | -42 |
| 5 | 313 |
| 6 | -3025 |
| 7 | 35091 |
| 8 | -482468 |
| 9 | 7704257 |
| 10 | -139729063 |
| 11 | 2834494245 |
| 12 | -63612631742 |
| 13 | 1564879314945 |
| 14 | -41866671551549 |
| 15 | 1210176423684151 |
| 16 | -37583615159233544 |
| 17 | 1248017801182054753 |
| 18 | -44124684998406215691 |
[0,1,-3,9,-42,313,-3025,35091,-482468,7704257, -139729063,2834494245,-63612631742,1564879314945, -41866671551549,1210176423684151, -37583615159233544,1248017801182054753, -44124684998406215691] |