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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | -7 |
| 2 | 42 |
| 3 | -259 |
| 4 | 1589 |
| 5 | -9758 |
| 6 | 59913 |
| 7 | -367871 |
| 8 | 2258746 |
| 9 | -13868827 |
| 10 | 85155357 |
| 11 | -522858574 |
| 12 | 3210380369 |
| 13 | -19711911863 |
| 14 | 121032221898 |
| 15 | -743144492531 |
| 16 | 4562948015941 |
| 17 | -28016751527422 |
| 18 | 172024393748697 |
| 19 | -1056239229435439 |
[1,-7,42,-259,1589,-9758,59913,-367871,2258746, -13868827,85155357,-522858574,3210380369, -19711911863,121032221898,-743144492531, 4562948015941,-28016751527422,172024393748697, -1056239229435439] |