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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | -1 |
| 4 | -7 |
| 5 | -7 |
| 6 | 73 |
| 7 | 335 |
| 8 | -687 |
| 9 | -12367 |
| 10 | -19471 |
| 11 | 461119 |
| 12 | 2839561 |
| 13 | -15282199 |
| 14 | -260138759 |
| 15 | -15084017 |
| 16 | 22560194593 |
| 17 | 113205762401 |
| 18 | -1856685484703 |
| 19 | -23353924295169 |
| 20 | 115492830956953 |
| 21 | 3999727786726617 |
| 22 | 5211807618131753 |
| 23 | -646193037236457649 |
[1,1,1,-1,-7,-7,73,335,-687,-12367,-19471,461119, 2839561,-15282199,-260138759,-15084017, 22560194593,113205762401,-1856685484703, -23353924295169,115492830956953,3999727786726617, 5211807618131753,-646193037236457649] |