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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 2 |
| 3 | -3 |
| 4 | 16 |
| 5 | -80 |
| 6 | 488 |
| 7 | -3339 |
| 8 | 26472 |
| 9 | -241128 |
| 10 | 2416002 |
| 11 | -26168835 |
| 12 | 310984452 |
| 13 | -4057771068 |
| 14 | 56774212350 |
| 15 | -841821751575 |
| 16 | 13356966503088 |
| 17 | -227284196307984 |
| 18 | 4085254725230514 |
| 19 | -76911822855270819 |
[1,0,2,-3,16,-80,488,-3339,26472,-241128,2416002, -26168835,310984452,-4057771068,56774212350, -841821751575,13356966503088,-227284196307984, 4085254725230514,-76911822855270819] |