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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 0 |
| 3 | 1 |
| 4 | 4 |
| 5 | 10 |
| 6 | 20 |
| 7 | 35 |
| 8 | 55 |
| 9 | 75 |
| 10 | 75 |
| 11 | 0 |
| 12 | -275 |
| 13 | -1000 |
| 14 | -2625 |
| 15 | -5875 |
| 16 | -11750 |
| 17 | -21250 |
| 18 | -34375 |
| 19 | -47500 |
| 20 | -47500 |
| 21 | 0 |
| 22 | 171875 |
| 23 | 621875 |
| 24 | 1628125 |
| 25 | 3640625 |
| 26 | 7281250 |
| 27 | 13171875 |
| 28 | 21312500 |
| 29 | 29453125 |
| 30 | 29453125 |
| 31 | 0 |
| 32 | -106562500 |
| 33 | -385546875 |
| 34 | -1009375000 |
| 35 | -2257031250 |
| 36 | -4514062500 |
[0,0,0,1,4,10,20,35,55,75,75,0,-275,-1000,-2625, -5875,-11750,-21250,-34375,-47500,-47500,0,171875, 621875,1628125,3640625,7281250,13171875,21312500, 29453125,29453125,0,-106562500,-385546875, -1009375000,-2257031250,-4514062500] |