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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 252 |
| 3 | 113400 |
| 4 | 141523200 |
| 5 | 373621248000 |
| 6 | 1788898535424000 |
| 7 | 14050009097220096000 |
| 8 | 168600109166641152000000 |
| 9 | 2931618698189556350976000000 |
| 10 | 70886540122223472566599680000000 |
| 11 | 2306506242496907350372020387840000000 |
| 12 | 98312522080188178902256997011292160000000 |
[3,252,113400,141523200,373621248000, 1788898535424000,14050009097220096000, 168600109166641152000000, 2931618698189556350976000000, 70886540122223472566599680000000, 2306506242496907350372020387840000000, 98312522080188178902256997011292160000000] |