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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | -2 |
| 3 | 5 |
| 4 | -19 |
| 5 | 104 |
| 6 | -706 |
| 7 | 5662 |
| 8 | -53082 |
| 9 | 570600 |
| 10 | -6897016 |
| 11 | 92565296 |
| 12 | -1366706848 |
| 13 | 22016867248 |
| 14 | -384226243584 |
| 15 | 7220865546000 |
| 16 | -145397565641296 |
| 17 | 3122890640031488 |
| 18 | -71266398589322368 |
| 19 | 1722010388581604224 |
[0,1,-2,5,-19,104,-706,5662,-53082,570600, -6897016,92565296,-1366706848,22016867248, -384226243584,7220865546000,-145397565641296, 3122890640031488,-71266398589322368, 1722010388581604224] |