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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | -6 |
| 3 | 32 |
| 4 | -210 |
| 5 | 1536 |
| 6 | -12012 |
| 7 | 98304 |
| 8 | -831402 |
| 9 | 7208960 |
| 10 | -63740820 |
| 11 | 572522496 |
| 12 | -5209363380 |
| 13 | 47915728896 |
| 14 | -444799488600 |
| 15 | 4161823309824 |
| 16 | -39209074920090 |
| 17 | 371626340253696 |
| 18 | -3541117629057540 |
| 19 | 33902753847705600 |
| 20 | -325969196485349340 |
| 21 | 3146175557067079680 |
| 22 | -30471769822097981160 |
[1,2,-6,32,-210,1536,-12012,98304,-831402,7208960, -63740820,572522496,-5209363380,47915728896, -444799488600,4161823309824,-39209074920090, 371626340253696,-3541117629057540, 33902753847705600,-325969196485349340, 3146175557067079680,-30471769822097981160] |