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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | -2 |
| 3 | 1 |
| 4 | -1 |
| 5 | 2 |
| 6 | -3 |
| 7 | 4 |
| 8 | -5 |
| 9 | 8 |
| 10 | -13 |
| 11 | 18 |
| 12 | -25 |
| 13 | 40 |
| 14 | -62 |
| 15 | 90 |
| 16 | -135 |
| 17 | 210 |
| 18 | -324 |
| 19 | 492 |
| 20 | -750 |
| 21 | 1164 |
| 22 | -1809 |
| 23 | 2786 |
| 24 | -4305 |
| 25 | 6710 |
| 26 | -10460 |
| 27 | 16264 |
| 28 | -25350 |
| 29 | 39650 |
| 30 | -62057 |
| 31 | 97108 |
| 32 | -152145 |
| 33 | 238818 |
| 34 | -375165 |
| 35 | 589520 |
| 36 | -927200 |
| 37 | 1459960 |
| 38 | -2300346 |
| 39 | 3626200 |
| 40 | -5720274 |
| 41 | 9030450 |
[1,1,-2,1,-1,2,-3,4,-5,8,-13,18,-25,40,-62,90, -135,210,-324,492,-750,1164,-1809,2786,-4305,6710, -10460,16264,-25350,39650,-62057,97108,-152145, 238818,-375165,589520,-927200,1459960,-2300346, 3626200,-5720274,9030450] |