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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | -1 |
| 3 | -1 |
| 4 | 9 |
| 5 | 9 |
| 6 | -73 |
| 7 | -73 |
| 8 | 697 |
| 9 | 697 |
| 10 | -7161 |
| 11 | -7161 |
| 12 | 77457 |
| 13 | 77457 |
| 14 | -868881 |
| 15 | -868881 |
| 16 | 10016241 |
| 17 | 10016241 |
| 18 | -117935473 |
| 19 | -117935473 |
| 20 | 1412307481 |
| 21 | 1412307481 |
| 22 | -17148100569 |
| 23 | -17148100569 |
| 24 | 210619695913 |
| 25 | 210619695913 |
| 26 | -2612194773481 |
| 27 | -2612194773481 |
| 28 | 32668519882017 |
| 29 | 32668519882017 |
| 30 | -411515480555553 |
[1,1,-1,-1,9,9,-73,-73,697,697,-7161,-7161,77457, 77457,-868881,-868881,10016241,10016241, -117935473,-117935473,1412307481,1412307481, -17148100569,-17148100569,210619695913, 210619695913,-2612194773481,-2612194773481, 32668519882017,32668519882017,-411515480555553] |