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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 108 |
| 3 | 228 |
| 4 | 13710 |
| 5 | 44790 |
| 6 | 6996920 |
| 7 | 11128712 |
| 8 | 12306056 |
| 9 | 3816547290 |
| 10 | 7838911147538198 |
[2,108,228,13710,44790,6996920,11128712,12306056, 3816547290,7838911147538198] |