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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 9 |
| 5 | 25 |
| 6 | 125 |
| 7 | 1323 |
| 8 | 18755 |
| 9 | 388143 |
| 10 | 11998517 |
| 11 | 573092271 |
| 12 | 41661958269 |
| 13 | 4471274578309 |
| 14 | 730746269407465 |
| 15 | 180950069008864743 |
[1,1,1,9,25,125,1323,18755,388143,11998517, 573092271,41661958269,4471274578309, 730746269407465,180950069008864743] |