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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | -1 |
| 2 | 1 |
| 3 | -3 |
| 4 | 3 |
| 5 | -5 |
| 6 | 9 |
| 7 | -11 |
| 8 | 19 |
| 9 | -29 |
| 10 | 41 |
| 11 | -67 |
| 12 | 99 |
| 13 | -149 |
| 14 | 233 |
| 15 | -347 |
| 16 | 531 |
| 17 | -813 |
| 18 | 1225 |
| 19 | -1875 |
| 20 | 2851 |
| 21 | -4325 |
| 22 | 6601 |
| 23 | -10027 |
| 24 | 15251 |
| 25 | -23229 |
| 26 | 35305 |
| 27 | -53731 |
| 28 | 81763 |
| 29 | -124341 |
| 30 | 189225 |
| 31 | -287867 |
| 32 | 437907 |
| 33 | -666317 |
| 34 | 1013641 |
| 35 | -1542131 |
| 36 | 2346275 |
| 37 | -3569413 |
| 38 | 5430537 |
| 39 | -8261963 |
| 40 | 12569363 |
| 41 | -19123037 |
| 42 | 29093289 |
[1,-1,1,-3,3,-5,9,-11,19,-29,41,-67,99,-149,233, -347,531,-813,1225,-1875,2851,-4325,6601,-10027, 15251,-23229,35305,-53731,81763,-124341,189225, -287867,437907,-666317,1013641,-1542131,2346275, -3569413,5430537,-8261963,12569363,-19123037, 29093289] |