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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | -2 |
| 3 | 4 |
| 4 | -8 |
| 5 | 14 |
| 6 | -22 |
| 7 | 28 |
| 8 | -14 |
| 9 | -80 |
| 10 | 420 |
| 11 | -1430 |
| 12 | 4128 |
| 13 | -10798 |
| 14 | 26176 |
| 15 | -59114 |
| 16 | 123442 |
| 17 | -232240 |
| 18 | 365888 |
| 19 | -355616 |
| 20 | -475892 |
| 21 | 4318112 |
| 22 | -17471288 |
| 23 | 56635490 |
| 24 | -163101656 |
| 25 | 432173038 |
| 26 | -1067080032 |
| 27 | 2456709054 |
| 28 | -5216642696 |
| 29 | 9906435640 |
| 30 | -15415122000 |
| 31 | 12937725806 |
| 32 | 33034018944 |
| 33 | -238942986520 |
[1,-2,4,-8,14,-22,28,-14,-80,420,-1430,4128, -10798,26176,-59114,123442,-232240,365888,-355616, -475892,4318112,-17471288,56635490,-163101656, 432173038,-1067080032,2456709054,-5216642696, 9906435640,-15415122000,12937725806,33034018944, -238942986520] |