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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 5 |
| 6 | 21 |
| 7 | 67 |
| 8 | 345 |
| 9 | 1649 |
| 10 | 10337 |
| 11 | 85161 |
| 12 | 930265 |
| 13 | 12022615 |
| 14 | 198707417 |
| 15 | 3901444367 |
[1,1,1,1,5,21,67,345,1649,10337,85161,930265, 12022615,198707417,3901444367] |