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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 11 |
| 5 | 32 |
| 6 | 134 |
| 7 | 711 |
| 8 | 5229 |
| 9 | 48736 |
| 10 | 543955 |
| 11 | 6799283 |
| 12 | 91500398 |
[1,2,4,11,32,134,711,5229,48736,543955,6799283, 91500398] |