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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 2 |
| 4 | 7 |
| 5 | 12 |
| 6 | 22 |
| 7 | 26 |
| 8 | 85 |
| 9 | 226 |
| 10 | 717 |
| 11 | 1695 |
| 12 | 5071 |
| 13 | 14275 |
| 14 | 47405 |
| 15 | 176747 |
| 16 | 638329 |
| 17 | 2166516 |
[1,1,2,2,7,12,22,26,85,226,717,1695,5071,14275, 47405,176747,638329,2166516] |