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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 4 |
| 5 | 5 |
| 6 | 6 |
| 7 | 7 |
| 8 | 8 |
| 9 | 9 |
| 10 | 63 |
| 11 | 448 |
| 12 | 1547 |
| 13 | 1693 |
| 14 | 6189068 |
| 15 | 20443796 |
| 16 | 67526389 |
[1,2,3,4,5,6,7,8,9,63,448,1547,1693,6189068, 20443796,67526389] |