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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 0 |
| 3 | 0 |
| 4 | 1 |
| 5 | 1 |
| 6 | 1 |
| 7 | 3 |
| 8 | 4 |
| 9 | 13 |
| 10 | 36 |
| 11 | 115 |
| 12 | 813 |
| 13 | 3083 |
| 14 | 21001 |
| 15 | 131859 |
| 16 | 868613 |
[1,0,0,1,1,1,3,4,13,36,115,813,3083,21001,131859, 868613] |