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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 1 |
| 7 | 5 |
| 8 | 21 |
| 9 | 39 |
| 10 | 165 |
| 11 | 631 |
| 12 | 2161 |
| 13 | 10045 |
| 14 | 71155 |
| 15 | 449909 |
[1,1,1,1,1,1,5,21,39,165,631,2161,10045,71155, 449909] |