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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | -1 |
| 3 | 1 |
| 4 | -4 |
| 5 | 17 |
| 6 | -86 |
| 7 | 514 |
| 8 | -3599 |
| 9 | 28809 |
| 10 | -259285 |
| 11 | 2592766 |
| 12 | -28520427 |
| 13 | 342245654 |
| 14 | -4449193503 |
| 15 | 62288705445 |
| 16 | -934330581764 |
| 17 | 14949289337033 |
| 18 | -254137918729562 |
| 19 | 4574482536873349 |
| 20 | -86915168200593632 |
| 21 | 1738303364014465422 |
| 22 | -36504370644303777464 |
| 23 | 803096154174654583783 |
| 24 | -18471211546017055427010 |
[1,-1,1,-4,17,-86,514,-3599,28809,-259285,2592766, -28520427,342245654,-4449193503,62288705445, -934330581764,14949289337033,-254137918729562, 4574482536873349,-86915168200593632, 1738303364014465422,-36504370644303777464, 803096154174654583783,-18471211546017055427010] |