The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | -1 |
| 3 | 5 |
| 4 | -18 |
| 5 | 121 |
| 6 | -792 |
| 7 | 7069 |
| 8 | -67088 |
| 9 | 763057 |
| 10 | -9443584 |
| 11 | 132103157 |
| 12 | -2008841472 |
| 13 | 33527321257 |
| 14 | -603694522368 |
| 15 | 11731117858573 |
| 16 | -243894274033664 |
| 17 | 5412661283979361 |
| 18 | -127565755034927104 |
| 19 | 3184128808387236581 |
[0,1,-1,5,-18,121,-792,7069,-67088,763057, -9443584,132103157,-2008841472,33527321257, -603694522368,11731117858573,-243894274033664, 5412661283979361,-127565755034927104, 3184128808387236581] |