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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 8 |
| 4 | 129 |
| 5 | 3216 |
| 6 | 108770 |
| 7 | 4638624 |
| 8 | 238318885 |
| 9 | 14304161568 |
| 10 | 981167968494 |
| 11 | 75656236536880 |
| 12 | 6474624435825546 |
| 13 | 608726166485138400 |
| 14 | 62351661805733365988 |
| 15 | 6910034200942823999216 |
| 16 | 823702177681649409615885 |
| 17 | 105083183676401369775220288 |
| 18 | 14284797856254053619382213974 |
[1,1,8,129,3216,108770,4638624,238318885, 14304161568,981167968494,75656236536880, 6474624435825546,608726166485138400, 62351661805733365988,6910034200942823999216, 823702177681649409615885, 105083183676401369775220288, 14284797856254053619382213974] |