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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 7 |
| 3 | 240 |
| 4 | 21720 |
| 5 | 3371661 |
| 6 | 753384764 |
| 7 | 221280081152 |
| 8 | 8057098267140 |
| 9 | 34901583348508312 |
| 10 | 17450751376913065040 |
| 11 | 9843352171270598267648 |
| 12 | 6153355867118768196316096 |
| 13 | 4203420758907186950461719325 |
| 14 | 3102284883642894954937435310820 |
[1,1,7,240,21720,3371661,753384764,221280081152, 8057098267140,34901583348508312, 17450751376913065040,9843352171270598267648, 6153355867118768196316096, 4203420758907186950461719325, 3102284883642894954937435310820] |