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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | -13 |
| 2 | 78 |
| 3 | -299 |
| 4 | 884 |
| 5 | -2314 |
| 6 | 5681 |
| 7 | -13052 |
| 8 | 28158 |
| 9 | -58136 |
| 10 | 116129 |
| 11 | -224692 |
| 12 | 422214 |
| 13 | -774372 |
| 14 | 1390948 |
| 15 | -2450565 |
| 16 | 4240561 |
| 17 | -7221383 |
| 18 | 12121980 |
| 19 | -20076953 |
| 20 | 32836752 |
| 21 | -53089309 |
| 22 | 84922877 |
| 23 | -134488770 |
| 24 | 210979548 |
[1,-13,78,-299,884,-2314,5681,-13052,28158,-58136, 116129,-224692,422214,-774372,1390948,-2450565, 4240561,-7221383,12121980,-20076953,32836752, -53089309,84922877,-134488770,210979548] |