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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 4 |
| 5 | 6 |
| 6 | 14 |
| 7 | 28 |
| 8 | 68 |
| 9 | 156 |
| 10 | 399 |
| 11 | 1012 |
| 12 | 2732 |
| 13 | 7385 |
| 14 | 20665 |
| 15 | 58377 |
| 16 | 168119 |
| 17 | 488771 |
[1,1,1,2,4,6,14,28,68,156,399,1012,2732,7385, 20665,58377,168119,488771] |