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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 8 |
| 3 | 1 |
| 4 | 241 |
| 5 | 748 |
| 6 | 16715 |
| 7 | 117067 |
| 8 | 1557684 |
| 9 | 14265803 |
| 10 | 161569614 |
| 11 | 1620282797 |
| 12 | 17408729025 |
| 13 | 179900894011 |
| 14 | 1900169117498 |
| 15 | 19826703745763 |
| 16 | 208284274385624 |
| 17 | 2179869985099525 |
| 18 | 22861530838829623 |
| 19 | 239488491429326898 |
[0,8,1,241,748,16715,117067,1557684,14265803, 161569614,1620282797,17408729025,179900894011, 1900169117498,19826703745763,208284274385624, 2179869985099525,22861530838829623, 239488491429326898] |