The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | -1 |
| 3 | 1 |
| 4 | -19 |
| 5 | 9 |
| 6 | -863 |
| 7 | 1375 |
| 8 | -33953 |
| 9 | 57281 |
| 10 | -3250433 |
| 11 | 1891755 |
| 12 | -13695779093 |
| 13 | 24466579093 |
| 14 | -132282840127 |
| 15 | 240208245823 |
| 16 | -111956703448001 |
| 17 | 4573423873125 |
| 18 | -30342376302478019 |
| 19 | 56310194579604163 |
| 20 | -12365722323469980029 |
| 21 | 161867055619224199787 |
| 22 | -20953816286242674495191 |
[1,1,-1,1,-19,9,-863,1375,-33953,57281,-3250433, 1891755,-13695779093,24466579093,-132282840127, 240208245823,-111956703448001,4573423873125, -30342376302478019,56310194579604163, -12365722323469980029,161867055619224199787, -20953816286242674495191] |