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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | -1 |
| 3 | 1 |
| 4 | -1 |
| 5 | 1 |
| 6 | 23 |
| 7 | -83 |
| 8 | 203 |
| 9 | -413 |
| 10 | 749 |
| 11 | 10843 |
| 12 | -70603 |
| 13 | 271573 |
| 14 | -816733 |
| 15 | 2102017 |
| 16 | 21579095 |
| 17 | -214325285 |
| 18 | 1126810565 |
| 19 | -4459081205 |
| 20 | 14750556437 |
| 21 | 110710301893 |
| 22 | -1576695251293 |
| 23 | 10568643559993 |
| 24 | -51770553894193 |
| 25 | 208509966593755 |
| 26 | 1135955939594837 |
| 27 | -22894350407438237 |
| 28 | 187765189943329037 |
[0,1,-1,1,-1,1,23,-83,203,-413,749,10843,-70603, 271573,-816733,2102017,21579095,-214325285, 1126810565,-4459081205,14750556437,110710301893, -1576695251293,10568643559993,-51770553894193, 208509966593755,1135955939594837, -22894350407438237,187765189943329037] |