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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 5 |
| 2 | 18 |
| 3 | 55 |
| 4 | 149 |
| 5 | 360 |
| 6 | 757 |
| 7 | 1265 |
| 8 | 1026 |
| 9 | -3725 |
| 10 | -25807 |
| 11 | -102960 |
| 12 | -334151 |
| 13 | -950035 |
| 14 | -2411118 |
| 15 | -5405345 |
| 16 | -10148899 |
| 17 | -12907080 |
| 18 | 6506893 |
| 19 | 122884025 |
| 20 | 568871874 |
| 21 | 1984171195 |
| 22 | 5938752857 |
| 23 | 15804565920 |
| 24 | 37451559601 |
| 25 | 76625836565 |
| 26 | 120968265618 |
| 27 | 68460472135 |
| 28 | -504475498651 |
[1,5,18,55,149,360,757,1265,1026,-3725,-25807, -102960,-334151,-950035,-2411118,-5405345, -10148899,-12907080,6506893,122884025,568871874, 1984171195,5938752857,15804565920,37451559601, 76625836565,120968265618,68460472135, -504475498651] |