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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 0 |
| 4 | -2 |
| 5 | 2 |
| 6 | 21 |
| 7 | -44 |
| 8 | -435 |
| 9 | 1416 |
| 10 | 14642 |
| 11 | -65280 |
| 12 | -726906 |
| 13 | 4134265 |
| 14 | 50048353 |
| 15 | -346876041 |
| 16 | -4571655884 |
| 17 | 37405303763 |
| 18 | 535496468325 |
| 19 | -5053938786250 |
| 20 | -78293577768981 |
| 21 | 837492552619032 |
| 22 | 13979476317110420 |
| 23 | -167167608081868420 |
| 24 | -2993817113886726927 |
| 25 | 39581544484714769732 |
[1,1,1,0,-2,2,21,-44,-435,1416,14642,-65280, -726906,4134265,50048353,-346876041,-4571655884, 37405303763,535496468325,-5053938786250, -78293577768981,837492552619032,13979476317110420, -167167608081868420,-2993817113886726927, 39581544484714769732] |