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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | -3 |
| 3 | -13 |
| 4 | 15 |
| 5 | -37 |
| 6 | 23 |
| 7 | -125 |
| 8 | -467 |
| 9 | -2269 |
| 10 | -2269 |
| 11 | -12147 |
| 12 | -66877 |
| 13 | -66877 |
| 14 | -66877 |
| 15 | -66877 |
| 16 | -370963 |
| 17 | -2061725 |
| 18 | -11464371 |
| 19 | 17899313 |
| 20 | 99555423 |
| 21 | 99555423 |
| 22 | -155471765 |
| 23 | -864636987 |
| 24 | 1350136841 |
| 25 | 1350136841 |
| 26 | -2108411107 |
| 27 | -2108411107 |
[0,1,-3,-13,15,-37,23,-125,-467,-2269,-2269, -12147,-66877,-66877,-66877,-66877,-370963, -2061725,-11464371,17899313,99555423,99555423, -155471765,-864636987,1350136841,1350136841, -2108411107,-2108411107] |