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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 7 |
| 4 | 62 |
| 5 | 324 |
| 6 | 1647 |
| 7 | 3566 |
| 8 | 5464 |
| 9 | 8655 |
| 10 | 8817 |
| 11 | 123956 |
| 12 | 132891 |
| 13 | 182098 |
| 14 | 566593 |
| 15 | 2189647 |
| 16 | 2189648 |
| 17 | 3501843 |
| 18 | 3501844 |
[1,2,7,62,324,1647,3566,5464,8655,8817,123956, 132891,182098,566593,2189647,2189648,3501843, 3501844] |