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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | -1 |
| 2 | 1 |
| 3 | -2 |
| 4 | 9 |
| 5 | -32 |
| 6 | 157 |
| 7 | -828 |
| 8 | 5481 |
| 9 | -35496 |
| 10 | 290649 |
| 11 | -2290840 |
| 12 | 22092829 |
| 13 | -204459452 |
| 14 | 2273871485 |
| 15 | -24119527604 |
| 16 | 303515669169 |
| 17 | -3629239434576 |
| 18 | 50931449481777 |
| 19 | -677485393669744 |
| 20 | 10484228007290613 |
| 21 | -153504673218503140 |
| 22 | 2595681901243781013 |
| 23 | -41471161060916985516 |
| 24 | 760471144497476539177 |
| 25 | -13162910847523759863288 |
[1,-1,1,-2,9,-32,157,-828,5481,-35496,290649, -2290840,22092829,-204459452,2273871485, -24119527604,303515669169,-3629239434576, 50931449481777,-677485393669744,10484228007290613, -153504673218503140,2595681901243781013, -41471161060916985516,760471144497476539177, -13162910847523759863288] |