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| n | a(n) |
|---|---|
| 1 | 8 |
| 2 | 69 |
| 3 | 374 |
| 4 | 2370 |
| 5 | 16508 |
| 6 | 109790 |
| 7 | 740555 |
| 8 | 5099557 |
| 9 | 35164860 |
| 10 | 243349752 |
| 11 | 1692155321 |
| 12 | 11793110356 |
| 13 | 82320111334 |
| 14 | 575444883737 |
| 15 | 4026374990333 |
| 16 | 28190847306569 |
| 17 | 197477547407507 |
| 18 | 1383825689115547 |
| 19 | 9699593987871364 |
| 20 | 67999308521067033 |
[8,69,374,2370,16508,109790,740555,5099557, 35164860,243349752,1692155321,11793110356, 82320111334,575444883737,4026374990333, 28190847306569,197477547407507,1383825689115547, 9699593987871364,67999308521067033] |