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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 9 |
| 3 | 52 |
| 4 | 463 |
| 5 | 5371 |
| 6 | 77320 |
| 7 | 1231170 |
| 8 | 20115063 |
| 9 | 319006954 |
| 10 | 4768598707 |
| 11 | 66353854322 |
| 12 | 856330630443 |
| 13 | 10262183989448 |
[2,9,52,463,5371,77320,1231170,20115063,319006954, 4768598707,66353854322,856330630443, 10262183989448] |