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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | -4 |
| 2 | 14 |
| 3 | -40 |
| 4 | 101 |
| 5 | -236 |
| 6 | 518 |
| 7 | -1080 |
| 8 | 2162 |
| 9 | -4180 |
| 10 | 7840 |
| 11 | -14328 |
| 12 | 25591 |
| 13 | -44776 |
| 14 | 76918 |
| 15 | -129952 |
| 16 | 216240 |
| 17 | -354864 |
| 18 | 574958 |
| 19 | -920600 |
| 20 | 1457946 |
| 21 | -2285452 |
| 22 | 3548550 |
| 23 | -5460592 |
| 24 | 8332425 |
| 25 | -12614088 |
| 26 | 18953310 |
| 27 | -28276968 |
| 28 | 41904208 |
| 29 | -61702876 |
| 30 | 90304598 |
| 31 | -131399624 |
[1,-4,14,-40,101,-236,518,-1080,2162,-4180,7840, -14328,25591,-44776,76918,-129952,216240,-354864, 574958,-920600,1457946,-2285452,3548550,-5460592, 8332425,-12614088,18953310,-28276968,41904208, -61702876,90304598,-131399624] |