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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | -2 |
| 2 | 2 |
| 3 | -2 |
| 4 | 4 |
| 5 | -10 |
| 6 | 22 |
| 7 | -44 |
| 8 | 86 |
| 9 | -170 |
| 10 | 340 |
| 11 | -682 |
| 12 | 1366 |
| 13 | -2732 |
| 14 | 5462 |
| 15 | -10922 |
| 16 | 21844 |
| 17 | -43690 |
| 18 | 87382 |
| 19 | -174764 |
| 20 | 349526 |
| 21 | -699050 |
| 22 | 1398100 |
| 23 | -2796202 |
| 24 | 5592406 |
| 25 | -11184812 |
| 26 | 22369622 |
| 27 | -44739242 |
| 28 | 89478484 |
| 29 | -178956970 |
| 30 | 357913942 |
| 31 | -715827884 |
| 32 | 1431655766 |
| 33 | -2863311530 |
[1,-2,2,-2,4,-10,22,-44,86,-170,340,-682,1366, -2732,5462,-10922,21844,-43690,87382,-174764, 349526,-699050,1398100,-2796202,5592406,-11184812, 22369622,-44739242,89478484,-178956970,357913942, -715827884,1431655766,-2863311530] |