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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 11 |
| 2 | 105 |
| 3 | 1020 |
| 4 | 10500 |
| 5 | 115920 |
| 6 | 1375920 |
| 7 | 17539200 |
| 8 | 239500800 |
| 9 | 3492720000 |
| 10 | 54226972800 |
| 11 | 893577484800 |
| 12 | 15583119552000 |
| 13 | 286816578048000 |
| 14 | 5557616064000000 |
| 15 | 113108602134528000 |
| 16 | 2412627824775168000 |
[1,11,105,1020,10500,115920,1375920,17539200, 239500800,3492720000,54226972800,893577484800, 15583119552000,286816578048000,5557616064000000, 113108602134528000,2412627824775168000] |