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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | -1 |
| 2 | 3 |
| 3 | -5 |
| 4 | 19 |
| 5 | -29 |
| 6 | 171 |
| 7 | -69 |
| 8 | 2339 |
| 9 | 5139 |
| 10 | 57563 |
| 11 | 303403 |
| 12 | 2397011 |
| 13 | 17237507 |
| 14 | 139011211 |
| 15 | 1151110299 |
| 16 | 10076637827 |
| 17 | 91903924979 |
| 18 | 874688607035 |
| 19 | 8656097294091 |
| 20 | 88932728790195 |
| 21 | 946748093175523 |
| 22 | 10426787247224043 |
| 23 | 118620906668843131 |
| 24 | 1392128306377939427 |
| 25 | 16833088095308098003 |
[1,-1,3,-5,19,-29,171,-69,2339,5139,57563,303403, 2397011,17237507,139011211,1151110299,10076637827, 91903924979,874688607035,8656097294091, 88932728790195,946748093175523,10426787247224043, 118620906668843131,1392128306377939427, 16833088095308098003] |