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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | -1 |
| 4 | 2 |
| 5 | 1 |
| 6 | 3 |
| 7 | -3 |
| 8 | 3 |
| 9 | 1 |
| 10 | -15 |
| 11 | 12 |
| 12 | -6 |
| 13 | 4 |
| 14 | 1 |
| 15 | 105 |
| 16 | -75 |
| 17 | 30 |
| 18 | -10 |
| 19 | 5 |
| 20 | 1 |
| 21 | -945 |
| 22 | 630 |
| 23 | -225 |
| 24 | 60 |
| 25 | -15 |
| 26 | 6 |
| 27 | 1 |
| 28 | 10395 |
| 29 | -6615 |
| 30 | 2205 |
| 31 | -525 |
| 32 | 105 |
| 33 | -21 |
| 34 | 7 |
| 35 | 1 |
| 36 | -135135 |
| 37 | 83160 |
| 38 | -26460 |
| 39 | 5880 |
| 40 | -1050 |
| 41 | 168 |
| 42 | -28 |
| 43 | 8 |
| 44 | 1 |
| 45 | 2027025 |
| 46 | -1216215 |
| 47 | 374220 |
| 48 | -79380 |
| 49 | 13230 |
| 50 | -1890 |
| 51 | 252 |
| 52 | -36 |
| 53 | 9 |
| 54 | 1 |
[1,1,1,-1,2,1,3,-3,3,1,-15,12,-6,4,1,105,-75,30, -10,5,1,-945,630,-225,60,-15,6,1,10395,-6615,2205, -525,105,-21,7,1,-135135,83160,-26460,5880,-1050, 168,-28,8,1,2027025,-1216215,374220,-79380,13230, -1890,252,-36,9,1] |