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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 5 |
| 6 | 17 |
| 7 | 61 |
| 8 | 319 |
| 9 | 1657 |
| 10 | 10301 |
| 11 | 78887 |
| 12 | 808895 |
| 13 | 10915803 |
| 14 | 187729525 |
| 15 | 3870401483 |
[1,1,1,1,5,17,61,319,1657,10301,78887,808895, 10915803,187729525,3870401483] |