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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 1 |
| 3 | -13 |
| 4 | -31 |
| 5 | 3 |
| 6 | 161 |
| 7 | 307 |
| 8 | -191 |
| 9 | -1917 |
| 10 | -2879 |
| 11 | 3827 |
| 12 | 22049 |
| 13 | 24963 |
| 14 | -60319 |
| 15 | -245453 |
| 16 | -189311 |
| 17 | 848643 |
| 18 | 2643841 |
| 19 | 1044467 |
| 20 | -11130271 |
| 21 | -27482877 |
| 22 | 685601 |
| 23 | 138785587 |
| 24 | 274143169 |
| 25 | -145641597 |
| 26 | -1661999039 |
| 27 | -2595790093 |
| 28 | 3118415009 |
| 29 | 19215780483 |
[1,3,1,-13,-31,3,161,307,-191,-1917,-2879,3827, 22049,24963,-60319,-245453,-189311,848643,2643841, 1044467,-11130271,-27482877,685601,138785587, 274143169,-145641597,-1661999039,-2595790093, 3118415009,19215780483] |