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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 12 |
| 5 | 47 |
| 6 | 267 |
| 7 | 1447 |
| 8 | 8590 |
| 9 | 51682 |
| 10 | 321146 |
| 11 | 2029853 |
| 12 | 13059614 |
| 13 | 85175835 |
| 14 | 562402901 |
[1,1,2,12,47,267,1447,8590,51682,321146,2029853, 13059614,85175835,562402901] |