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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | -2 |
| 4 | -3 |
| 5 | 2 |
| 6 | 15 |
| 7 | 51 |
| 8 | 65 |
| 9 | 27 |
| 10 | 6 |
| 11 | -148 |
| 12 | -945 |
| 13 | -2292 |
| 14 | -2776 |
| 15 | -1680 |
| 16 | -405 |
| 17 | 24 |
| 18 | 2290 |
| 19 | 19580 |
| 20 | 71965 |
| 21 | 145525 |
| 22 | 175244 |
| 23 | 125950 |
| 24 | 50085 |
| 25 | 8505 |
| 26 | 120 |
| 27 | -41676 |
| 28 | -473072 |
| 29 | -2340400 |
| 30 | -6676835 |
| 31 | -12132890 |
| 32 | -14587261 |
| 33 | -11619692 |
| 34 | -5290005 |
| 35 | -1752030 |
| 36 | -229635 |
| 37 | 720 |
| 38 | 943908 |
| 39 | 13132532 |
| 40 | 81977672 |
| 41 | 303352938 |
| 42 | 740797855 |
[1,1,-2,-3,2,15,51,65,27,6,-148,-945,-2292,-2776, -1680,-405,24,2290,19580,71965,145525,175244, 125950,50085,8505,120,-41676,-473072,-2340400, -6676835,-12132890,-14587261,-11619692,-5290005, -1752030,-229635,720,943908,13132532,81977672, 303352938,740797855] |