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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | -3 |
| 3 | 3 |
| 4 | -6 |
| 5 | 9 |
| 6 | -15 |
| 7 | 21 |
| 8 | -33 |
| 9 | 48 |
| 10 | -75 |
| 11 | 111 |
| 12 | -168 |
| 13 | 252 |
| 14 | -381 |
| 15 | 570 |
| 16 | -858 |
| 17 | 1287 |
| 18 | -1932 |
| 19 | 2898 |
| 20 | -4350 |
| 21 | 6525 |
| 22 | -9789 |
| 23 | 14682 |
| 24 | -22026 |
| 25 | 33039 |
| 26 | -49560 |
| 27 | 74340 |
| 28 | -111513 |
| 29 | 167268 |
| 30 | -250905 |
| 31 | 376356 |
| 32 | -564537 |
| 33 | 846804 |
| 34 | -1270209 |
| 35 | 1905312 |
| 36 | -2857971 |
| 37 | 4286955 |
| 38 | -6430434 |
| 39 | 9645651 |
[0,0,-3,3,-6,9,-15,21,-33,48,-75,111,-168,252, -381,570,-858,1287,-1932,2898,-4350,6525,-9789, 14682,-22026,33039,-49560,74340,-111513,167268, -250905,376356,-564537,846804,-1270209,1905312, -2857971,4286955,-6430434,9645651] |