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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 2 |
| 3 | 0 |
| 4 | -16 |
| 5 | -52 |
| 6 | 200 |
| 7 | 3752 |
| 8 | 18496 |
| 9 | -190384 |
| 10 | -4797152 |
| 11 | -28063552 |
| 12 | 661457920 |
| 13 | 17348360768 |
| 14 | 74504846208 |
| 15 | -4999196993152 |
| 16 | -124352680593408 |
| 17 | -83620707815168 |
| 18 | 65968266617811456 |
| 19 | 1541961961341134848 |
[0,1,2,0,-16,-52,200,3752,18496,-190384,-4797152, -28063552,661457920,17348360768,74504846208, -4999196993152,-124352680593408,-83620707815168, 65968266617811456,1541961961341134848] |