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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 8 |
| 3 | 61 |
| 4 | 1339 |
| 5 | 27497 |
| 6 | 700526 |
| 7 | 20738540 |
| 8 | 701018049 |
| 9 | 26600152925 |
| 10 | 1118837321664 |
| 11 | 51638294897821 |
| 12 | 2593507095707555 |
| 13 | 140767051300283971 |
| 14 | 8208477680892328056 |
| 15 | 511665532350037672814 |
| 16 | 33945069368611365210831 |
| 17 | 2387678179967017695888746 |
| 18 | 177467827693197791991904437 |
[1,0,8,61,1339,27497,700526,20738540,701018049, 26600152925,1118837321664,51638294897821, 2593507095707555,140767051300283971, 8208477680892328056,511665532350037672814, 33945069368611365210831,2387678179967017695888746, 177467827693197791991904437] |