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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | -1 |
| 5 | 3 |
| 6 | -5 |
| 7 | 7 |
| 8 | -7 |
| 9 | 3 |
| 10 | 5 |
| 11 | -9 |
| 12 | -17 |
| 13 | 129 |
| 14 | -417 |
| 15 | 977 |
| 16 | -1809 |
| 17 | 2591 |
| 18 | -2317 |
| 19 | -1061 |
| 20 | 10485 |
| 21 | -27983 |
| 22 | 49165 |
| 23 | -51319 |
| 24 | -26861 |
| 25 | 311455 |
| 26 | -1011473 |
| 27 | 2393275 |
| 28 | -4643591 |
| 29 | 7521265 |
| 30 | -9694135 |
| 31 | 7738137 |
| 32 | 4976985 |
| 33 | -38789975 |
| 34 | 106112817 |
| 35 | -215068927 |
| 36 | 354515933 |
| 37 | -464539803 |
[1,1,1,1,-1,3,-5,7,-7,3,5,-9,-17,129,-417,977, -1809,2591,-2317,-1061,10485,-27983,49165,-51319, -26861,311455,-1011473,2393275,-4643591,7521265, -9694135,7738137,4976985,-38789975,106112817, -215068927,354515933,-464539803] |