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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 8 |
| 3 | 228 |
| 4 | 21625 |
| 5 | 6947036 |
| 6 | 7530280825 |
| 7 | 27552364197684 |
| 8 | 340198731046937302 |
| 9 | 14168448763536007733003 |
[1,8,228,21625,6947036,7530280825,27552364197684, 340198731046937302,14168448763536007733003] |