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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | -1 |
| 3 | 2 |
| 4 | -4 |
| 5 | 1 |
| 6 | 6 |
| 7 | -16 |
| 8 | 8 |
| 9 | -1 |
| 10 | 36 |
| 11 | -108 |
| 12 | 69 |
| 13 | -15 |
| 14 | 1 |
| 15 | 360 |
| 16 | -1152 |
| 17 | 834 |
| 18 | -230 |
| 19 | 26 |
| 20 | -1 |
| 21 | 6120 |
| 22 | -20304 |
| 23 | 15726 |
| 24 | -4890 |
| 25 | 693 |
| 26 | -44 |
| 27 | 1 |
| 28 | 171360 |
| 29 | -580752 |
| 30 | 467724 |
| 31 | -155524 |
| 32 | 24797 |
| 33 | -1963 |
| 34 | 73 |
| 35 | -1 |
| 36 | 7882560 |
| 37 | -27057312 |
| 38 | 22300752 |
| 39 | -7709504 |
[1,-1,2,-4,1,6,-16,8,-1,36,-108,69,-15,1,360, -1152,834,-230,26,-1,6120,-20304,15726,-4890,693, -44,1,171360,-580752,467724,-155524,24797,-1963, 73,-1,7882560,-27057312,22300752,-7709504] |