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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 1 |
| 3 | 1 |
| 4 | -1 |
| 5 | 3 |
| 6 | -9 |
| 7 | 23 |
| 8 | -53 |
| 9 | 115 |
| 10 | -237 |
| 11 | 457 |
| 12 | -801 |
| 13 | 1213 |
| 14 | -1389 |
| 15 | 445 |
| 16 | 3667 |
| 17 | -15081 |
| 18 | 41335 |
| 19 | -95059 |
| 20 | 195769 |
| 21 | -370803 |
| 22 | 652463 |
| 23 | -1063359 |
| 24 | 1570205 |
| 25 | -1961755 |
| 26 | 1560269 |
| 27 | 1401991 |
| 28 | -11023119 |
| 29 | 36000427 |
| 30 | -93408425 |
| 31 | 214275735 |
| 32 | -450374071 |
[2,1,1,-1,3,-9,23,-53,115,-237,457,-801,1213, -1389,445,3667,-15081,41335,-95059,195769,-370803, 652463,-1063359,1570205,-1961755,1560269,1401991, -11023119,36000427,-93408425,214275735,-450374071] |