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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | -1 |
| 2 | -1 |
| 3 | 0 |
| 4 | 3 |
| 5 | 6 |
| 6 | -9 |
| 7 | -90 |
| 8 | -153 |
| 9 | 1134 |
| 10 | 8019 |
| 11 | 2430 |
| 12 | -262197 |
| 13 | -1438074 |
| 14 | 4421871 |
| 15 | 104152230 |
| 16 | 380788047 |
| 17 | -4779057186 |
| 18 | -63944168661 |
| 19 | -55095931890 |
| 20 | 5848795071603 |
| 21 | 54270718742646 |
| 22 | -229189662998649 |
| 23 | -9171963685125450 |
| 24 | -53834845287495753 |
| 25 | 893621501807183694 |
[1,-1,-1,0,3,6,-9,-90,-153,1134,8019,2430,-262197, -1438074,4421871,104152230,380788047,-4779057186, -63944168661,-55095931890,5848795071603, 54270718742646,-229189662998649,-9171963685125450, -53834845287495753,893621501807183694] |