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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 4 |
| 3 | -6 |
| 4 | 91 |
| 5 | -470 |
| 6 | 6004 |
| 7 | -57057 |
| 8 | 807281 |
| 9 | -10925316 |
| 10 | 181019254 |
| 11 | -3109774415 |
| 12 | 60388378207 |
| 13 | -1243237163142 |
| 14 | 27924671116008 |
| 15 | -666732185288925 |
| 16 | 17061240258678497 |
| 17 | -462532118657434344 |
| 18 | 13300045106193385114 |
[1,0,4,-6,91,-470,6004,-57057,807281,-10925316, 181019254,-3109774415,60388378207,-1243237163142, 27924671116008,-666732185288925,17061240258678497, -462532118657434344,13300045106193385114] |