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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 13 |
| 3 | -11 |
| 4 | 217 |
| 5 | -599 |
| 6 | 4453 |
| 7 | -17891 |
| 8 | 102577 |
| 9 | -473519 |
| 10 | 2485693 |
| 11 | -12074171 |
| 12 | 61433737 |
| 13 | -303980039 |
| 14 | 1529466133 |
| 15 | -7618632851 |
| 16 | 38179257697 |
| 17 | -190638008159 |
| 18 | 953964881773 |
| 19 | -4767499885931 |
| 20 | 23844472998457 |
| 21 | -119201444285879 |
| 22 | 596069983548613 |
| 23 | -2980161631385411 |
[1,1,13,-11,217,-599,4453,-17891,102577,-473519, 2485693,-12074171,61433737,-303980039,1529466133, -7618632851,38179257697,-190638008159, 953964881773,-4767499885931,23844472998457, -119201444285879,596069983548613, -2980161631385411] |