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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 5 |
| 6 | 21 |
| 7 | 63 |
| 8 | 331 |
| 9 | 1837 |
| 10 | 11817 |
| 11 | 91941 |
| 12 | 951301 |
| 13 | 13059325 |
| 14 | 223458589 |
| 15 | 4681971763 |
[1,1,1,1,5,21,63,331,1837,11817,91941,951301, 13059325,223458589,4681971763] |