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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | -2 |
| 2 | 2 |
| 3 | -4 |
| 4 | 4 |
| 5 | -8 |
| 6 | 8 |
| 7 | -16 |
| 8 | 16 |
| 9 | -32 |
| 10 | 32 |
| 11 | -64 |
| 12 | 64 |
| 13 | -128 |
| 14 | 128 |
| 15 | -256 |
| 16 | 256 |
| 17 | -512 |
| 18 | 512 |
| 19 | -1024 |
| 20 | 1024 |
| 21 | -2048 |
| 22 | 2048 |
| 23 | -4096 |
| 24 | 4096 |
| 25 | -8192 |
| 26 | 8192 |
| 27 | -16384 |
| 28 | 16384 |
| 29 | -32768 |
| 30 | 32768 |
| 31 | -65536 |
| 32 | 65536 |
| 33 | -131072 |
| 34 | 131072 |
| 35 | -262144 |
| 36 | 262144 |
| 37 | -524288 |
| 38 | 524288 |
| 39 | -1048576 |
| 40 | 1048576 |
[1,-2,2,-4,4,-8,8,-16,16,-32,32,-64,64,-128,128, -256,256,-512,512,-1024,1024,-2048,2048,-4096, 4096,-8192,8192,-16384,16384,-32768,32768,-65536, 65536,-131072,131072,-262144,262144,-524288, 524288,-1048576,1048576] |