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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 9 |
| 5 | 25 |
| 6 | 125 |
| 7 | 1331 |
| 8 | 18779 |
| 9 | 389231 |
| 10 | 11969301 |
| 11 | 573650431 |
| 12 | 41782304071 |
| 13 | 4475707668912 |
| 14 | 731606853804073 |
| 15 | 181071469572900858 |
[1,1,1,9,25,125,1331,18779,389231,11969301, 573650431,41782304071,4475707668912, 731606853804073,181071469572900858] |