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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 0 |
| 3 | -20 |
| 4 | -221 |
| 5 | -1560 |
| 6 | 0 |
| 7 | 272000 |
| 8 | 6356025 |
| 9 | 84086080 |
| 10 | 0 |
| 11 | -40560998400 |
| 12 | -1449723503125 |
| 13 | -28152429760000 |
| 14 | 0 |
| 15 | 26582971351040000 |
| 16 | 1279483892211136625 |
| 17 | 32774236110420480000 |
| 18 | 0 |
| 19 | -51128938217766256640000 |
| 20 | -3094745459011904478178125 |
| 21 | -98456230888859903488000000 |
| 22 | 0 |
| 23 | 229377281607595274010624000000 |
[1,1,0,-20,-221,-1560,0,272000,6356025,84086080,0, -40560998400,-1449723503125,-28152429760000,0, 26582971351040000,1279483892211136625, 32774236110420480000,0,-51128938217766256640000, -3094745459011904478178125, -98456230888859903488000000,0, 229377281607595274010624000000] |