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| n | a(n) |
|---|---|
| 2 | 2 |
| 3 | 2 |
| 4 | 107 |
| 5 | 1657 |
| 6 | 25453 |
| 7 | 404819 |
| 8 | 1388449 |
| 9 | 137414987 |
| 10 | 402301129 |
| 11 | 87241770523 |
[2,2,107,1657,25453,404819,1388449,137414987, 402301129,87241770523] |