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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | -3 |
| 3 | -17 |
| 4 | 145 |
| 5 | 1401 |
| 6 | -19619 |
| 7 | -267833 |
| 8 | 5214273 |
| 9 | 91975825 |
| 10 | -2292948899 |
| 11 | -49586832129 |
| 12 | 1506939887377 |
| 13 | 38595456391753 |
| 14 | -1383612408628995 |
| 15 | -40951481342092649 |
| 16 | 1691614670048805121 |
| 17 | 56809502720559644577 |
| 18 | -2656760323700732460227 |
| 19 | -99810124102484722532465 |
[1,1,-3,-17,145,1401,-19619,-267833,5214273, 91975825,-2292948899,-49586832129,1506939887377, 38595456391753,-1383612408628995, -40951481342092649,1691614670048805121, 56809502720559644577,-2656760323700732460227, -99810124102484722532465] |