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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 8 |
| 3 | 170 |
| 4 | 9513 |
| 5 | 1489357 |
| 6 | 611929512 |
| 7 | 703696012516 |
| 8 | 2224035714999860 |
| 9 | 19157046204651408615 |
[1,8,170,9513,1489357,611929512,703696012516, 2224035714999860,19157046204651408615] |