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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 8 |
| 3 | 252 |
| 4 | 31012 |
| 5 | 14905344 |
| 6 | 27990353344 |
| 7 | 205353183605152 |
| 8 | 5886041167193603328 |
| 9 | 659134453175183361984192 |
| 10 | 288372301975051917749449831520 |
| 11 | 492903495313227230995120900845724672 |
[1,8,252,31012,14905344,27990353344, 205353183605152,5886041167193603328, 659134453175183361984192, 288372301975051917749449831520, 492903495313227230995120900845724672] |