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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | -2 |
| 3 | -4 |
| 4 | 4 |
| 5 | 48 |
| 6 | -160 |
| 7 | -32 |
| 8 | 2176 |
| 9 | 6912 |
| 10 | 0 |
| 11 | -273408 |
| 12 | 41984 |
| 13 | 19456 |
| 14 | -37027840 |
| 15 | -141705216 |
| 16 | 0 |
| 17 | 3833856 |
| 18 | -34359869440 |
| 19 | 0 |
| 20 | 1625620480000 |
| 21 | 11045440585728 |
| 22 | -47710208 |
| 23 | -520279482695680 |
| 24 | 7719016726528 |
| 25 | 909115392000 |
| 26 | -207717914210467840 |
| 27 | 0 |
| 28 | 0 |
| 29 | 100736516652659638272 |
| 30 | -721057900040447590400 |
[1,-2,-4,4,48,-160,-32,2176,6912,0,-273408,41984, 19456,-37027840,-141705216,0,3833856,-34359869440, 0,1625620480000,11045440585728,-47710208, -520279482695680,7719016726528,909115392000, -207717914210467840,0,0,100736516652659638272, -721057900040447590400] |