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| n | a(n) |
|---|---|
| 2 | 1 |
| 3 | 9 |
| 4 | 143 |
| 5 | 2699 |
| 6 | 199095 |
| 7 | 14042731 |
| 8 | 3855890801 |
| 9 | 1030417772377 |
| 10 | 1084629728348393 |
[1,9,143,2699,199095,14042731,3855890801, 1030417772377,1084629728348393] |