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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | -1 |
| 3 | 3 |
| 4 | -5 |
| 5 | 1 |
| 6 | 15 |
| 7 | -31 |
| 8 | 14 |
| 9 | -1 |
| 10 | 105 |
| 11 | -247 |
| 12 | 157 |
| 13 | -30 |
| 14 | 1 |
| 15 | 945 |
| 16 | -2433 |
| 17 | 1892 |
| 18 | -553 |
| 19 | 55 |
| 20 | -1 |
| 21 | 10395 |
| 22 | -28653 |
| 23 | 25573 |
| 24 | -9620 |
| 25 | 1554 |
| 26 | -91 |
| 27 | 1 |
| 28 | 135135 |
| 29 | -393279 |
| 30 | 388810 |
| 31 | -173773 |
| 32 | 37550 |
| 33 | -3738 |
| 34 | 140 |
| 35 | -1 |
| 36 | 2027025 |
| 37 | -6169455 |
[1,-1,3,-5,1,15,-31,14,-1,105,-247,157,-30,1,945, -2433,1892,-553,55,-1,10395,-28653,25573,-9620, 1554,-91,1,135135,-393279,388810,-173773,37550, -3738,140,-1,2027025,-6169455] |