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| n | a(n) |
|---|---|
| 0 | -2 |
| 1 | -1 |
| 2 | 1 |
| 3 | 2 |
| 4 | -5 |
| 5 | -16 |
| 6 | 61 |
| 7 | 272 |
| 8 | -1385 |
| 9 | -7936 |
| 10 | 50521 |
| 11 | 353792 |
| 12 | -2702765 |
| 13 | -22368256 |
| 14 | 199360981 |
| 15 | 1903757312 |
| 16 | -19391512145 |
| 17 | -209865342976 |
| 18 | 2404879675441 |
| 19 | 29088885112832 |
| 20 | -370371188237525 |
| 21 | -4951498053124096 |
| 22 | 69348874393137901 |
[-2,-1,1,2,-5,-16,61,272,-1385,-7936,50521,353792, -2702765,-22368256,199360981,1903757312, -19391512145,-209865342976,2404879675441, 29088885112832,-370371188237525,-4951498053124096, 69348874393137901] |