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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 6 |
| 5 | 16 |
| 6 | 36 |
| 7 | 83 |
| 8 | 190 |
| 9 | 448 |
| 10 | 1056 |
| 11 | 2514 |
| 12 | 5872 |
| 13 | 13806 |
| 14 | 32424 |
| 15 | 76609 |
| 16 | 181434 |
| 17 | 432062 |
| 18 | 1032716 |
[1,1,2,3,6,16,36,83,190,448,1056,2514,5872,13806, 32424,76609,181434,432062,1032716] |