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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | -1 |
| 3 | -5 |
| 4 | 1 |
| 5 | 161 |
| 6 | 31 |
| 7 | -8021 |
| 8 | -14335 |
| 9 | 686881 |
| 10 | 2925631 |
| 11 | -91860229 |
| 12 | -583959551 |
| 13 | 15741408385 |
| 14 | 169511794271 |
| 15 | -3832934048789 |
| 16 | -54596554106879 |
| 17 | 1106568438159809 |
| 18 | 23024933751472255 |
| 19 | -412744343093399429 |
| 20 | -11208399032299519999 |
| 21 | 177909311974519181281 |
[1,1,-1,-5,1,161,31,-8021,-14335,686881,2925631, -91860229,-583959551,15741408385,169511794271, -3832934048789,-54596554106879,1106568438159809, 23024933751472255,-412744343093399429, -11208399032299519999,177909311974519181281] |