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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 2 |
| 6 | 2 |
| 7 | 2 |
| 8 | 6 |
| 9 | 10 |
| 10 | 31 |
| 11 | 77 |
| 12 | 206 |
| 13 | 568 |
| 14 | 1704 |
| 15 | 5037 |
| 16 | 15554 |
[0,1,1,1,2,2,2,6,10,31,77,206,568,1704,5037,15554] |