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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | -7 |
| 2 | 36 |
| 3 | -173 |
| 4 | 827 |
| 5 | -3960 |
| 6 | 18973 |
| 7 | -90907 |
| 8 | 435564 |
| 9 | -2086913 |
| 10 | 9998999 |
| 11 | -47908080 |
| 12 | 229541401 |
| 13 | -1099798927 |
| 14 | 5269453236 |
| 15 | -25247467253 |
| 16 | 120967883027 |
| 17 | -579591947880 |
| 18 | 2776991856373 |
| 19 | -13305367333987 |
| 20 | 63749844813564 |
| 21 | -305443856733833 |
| 22 | 1463469438855599 |
| 23 | -7011903337544160 |
[1,-7,36,-173,827,-3960,18973,-90907,435564, -2086913,9998999,-47908080,229541401,-1099798927, 5269453236,-25247467253,120967883027, -579591947880,2776991856373,-13305367333987, 63749844813564,-305443856733833,1463469438855599, -7011903337544160] |