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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | -1 |
| 2 | 2 |
| 3 | 0 |
| 4 | 8 |
| 5 | 16 |
| 6 | 64 |
| 7 | 192 |
| 8 | 640 |
| 9 | 2048 |
| 10 | 6656 |
| 11 | 21504 |
| 12 | 69632 |
| 13 | 225280 |
| 14 | 729088 |
| 15 | 2359296 |
| 16 | 7634944 |
| 17 | 24707072 |
| 18 | 79953920 |
| 19 | 258736128 |
| 20 | 837287936 |
| 21 | 2709520384 |
| 22 | 8768192512 |
| 23 | 28374466560 |
| 24 | 91821703168 |
| 25 | 297141272576 |
| 26 | 961569357824 |
| 27 | 3111703805952 |
| 28 | 10069685043200 |
| 29 | 32586185310208 |
| 30 | 105451110793216 |
[1,-1,2,0,8,16,64,192,640,2048,6656,21504,69632, 225280,729088,2359296,7634944,24707072,79953920, 258736128,837287936,2709520384,8768192512, 28374466560,91821703168,297141272576,961569357824, 3111703805952,10069685043200,32586185310208, 105451110793216] |