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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 1 |
| 4 | 6 |
| 5 | 100 |
| 6 | 3285 |
| 7 | 177471 |
| 8 | 14188888 |
| 9 | 1569185136 |
| 10 | 229087571625 |
| 11 | 42657089362525 |
| 12 | 9865968972312816 |
| 13 | 2775121127493066144 |
| 14 | 933088633696985015341 |
| 15 | 369664023805893580624875 |
| 16 | 170462028446539785915840000 |
| 17 | 90535875809937268263059201536 |
| 18 | 54880459059177867635557856462097 |
[0,1,1,6,100,3285,177471,14188888,1569185136, 229087571625,42657089362525,9865968972312816, 2775121127493066144,933088633696985015341, 369664023805893580624875, 170462028446539785915840000, 90535875809937268263059201536, 54880459059177867635557856462097] |