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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 1 |
| 4 | -11 |
| 5 | 61 |
| 6 | 301 |
| 7 | -6299 |
| 8 | 7561 |
| 9 | 903673 |
| 10 | -9019079 |
| 11 | -145636919 |
| 12 | 4305630781 |
| 13 | 7516191541 |
| 14 | -2037845181371 |
| 15 | 22442805921901 |
| 16 | 944219385367441 |
| 17 | -29922880660473359 |
| 18 | -288352494154313999 |
| 19 | 32071808922904896913 |
| 20 | -273044292430852251899 |
[1,1,3,1,-11,61,301,-6299,7561,903673,-9019079, -145636919,4305630781,7516191541,-2037845181371, 22442805921901,944219385367441,-29922880660473359, -288352494154313999,32071808922904896913, -273044292430852251899] |