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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | -1 |
| 2 | -4 |
| 3 | -1 |
| 4 | 21 |
| 5 | 29 |
| 6 | -80 |
| 7 | -244 |
| 8 | 153 |
| 9 | 1473 |
| 10 | 836 |
| 11 | -6920 |
| 12 | -12220 |
| 13 | 23209 |
| 14 | 91213 |
| 15 | -21511 |
| 16 | -510680 |
| 17 | -457965 |
| 18 | 2210520 |
| 19 | 4921941 |
| 20 | -6271749 |
| 21 | -33288595 |
| 22 | -3876765 |
| 23 | 173223185 |
| 24 | 214943855 |
| 25 | -682969376 |
| 26 | -1912499375 |
| 27 | 1498348275 |
| 28 | 11882164650 |
| 29 | 5332839025 |
| 30 | -57402248250 |
| 31 | -92821609874 |
[1,-1,-4,-1,21,29,-80,-244,153,1473,836,-6920, -12220,23209,91213,-21511,-510680,-457965,2210520, 4921941,-6271749,-33288595,-3876765,173223185, 214943855,-682969376,-1912499375,1498348275, 11882164650,5332839025,-57402248250,-92821609874] |