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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | -1 |
| 4 | -7 |
| 5 | -16 |
| 6 | 19 |
| 7 | 270 |
| 8 | 809 |
| 9 | -1832 |
| 10 | -26939 |
| 11 | -81680 |
| 12 | 415817 |
| 13 | 5085192 |
| 14 | 11943199 |
| 15 | -154023064 |
| 16 | -1510744111 |
| 17 | -1192784896 |
| 18 | 80798373289 |
| 19 | 615743987520 |
| 20 | -1348945040647 |
| 21 | -55570193758592 |
| 22 | -296824726927253 |
| 23 | 2567750854163200 |
| 24 | 47111874571146041 |
[1,1,1,-1,-7,-16,19,270,809,-1832,-26939,-81680, 415817,5085192,11943199,-154023064,-1510744111, -1192784896,80798373289,615743987520, -1348945040647,-55570193758592,-296824726927253, 2567750854163200,47111874571146041] |