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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | -1 |
| 3 | -2 |
| 4 | 0 |
| 5 | 250 |
| 6 | 5616 |
| 7 | -33614 |
| 8 | 0 |
| 9 | 204073344 |
| 10 | -900000000 |
| 11 | -9431790764 |
| 12 | 0 |
| 13 | 10752962364222 |
| 14 | -1870899108384768 |
| 15 | -36328974609375000 |
| 16 | 0 |
| 17 | 22899384412078526344 |
| 18 | -111400529859275793629184 |
| 19 | -43843094862278417487512 |
| 20 | 0 |
| 21 | 2870507605405055660542502550 |
| 22 | 67015802375208384199755038720 |
[1,0,-1,-2,0,250,5616,-33614,0,204073344, -900000000,-9431790764,0,10752962364222, -1870899108384768,-36328974609375000,0, 22899384412078526344,-111400529859275793629184, -43843094862278417487512,0, 2870507605405055660542502550, 67015802375208384199755038720] |