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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | -1 |
| 3 | 0 |
| 4 | 3 |
| 5 | -8 |
| 6 | 12 |
| 7 | -6 |
| 8 | -37 |
| 9 | 208 |
| 10 | -730 |
| 11 | 1708 |
| 12 | -1278 |
| 13 | -10018 |
| 14 | 56782 |
| 15 | -163644 |
| 16 | 229985 |
| 17 | 389830 |
| 18 | -3724538 |
| 19 | 13460550 |
| 20 | -28799694 |
| 21 | 12470564 |
| 22 | 205544596 |
| 23 | -1084748334 |
| 24 | 3195484242 |
| 25 | -4851317704 |
| 26 | -7421547798 |
| 27 | 81343472008 |
[1,-1,0,3,-8,12,-6,-37,208,-730,1708,-1278,-10018, 56782,-163644,229985,389830,-3724538,13460550, -28799694,12470564,205544596,-1084748334, 3195484242,-4851317704,-7421547798,81343472008] |