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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 10 |
| 5 | 31 |
| 6 | 153 |
| 7 | 703 |
| 8 | 3393 |
| 9 | 16001 |
| 10 | 75381 |
| 11 | 357369 |
| 12 | 1713043 |
| 13 | 8299559 |
| 14 | 40613618 |
| 15 | 200412275 |
| 16 | 995895544 |
[1,2,3,10,31,153,703,3393,16001,75381,357369, 1713043,8299559,40613618,200412275,995895544] |