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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 5 |
| 3 | 0 |
| 4 | 21 |
| 5 | 0 |
| 6 | 85 |
| 7 | 0 |
| 8 | 341 |
| 9 | 0 |
| 10 | 1365 |
| 11 | 0 |
| 12 | 5461 |
| 13 | 0 |
| 14 | 21845 |
| 15 | 0 |
| 16 | 87381 |
| 17 | 0 |
| 18 | 349525 |
| 19 | 0 |
| 20 | 1398101 |
| 21 | 0 |
| 22 | 5592405 |
| 23 | 0 |
| 24 | 22369621 |
| 25 | 0 |
| 26 | 89478485 |
| 27 | 0 |
| 28 | 357913941 |
| 29 | 0 |
| 30 | 1431655765 |
| 31 | 0 |
| 32 | 5726623061 |
| 33 | 0 |
| 34 | 22906492245 |
| 35 | 0 |
| 36 | 91625968981 |
| 37 | 0 |
| 38 | 366503875925 |
| 39 | 0 |
| 40 | 1466015503701 |
| 41 | 0 |
| 42 | 5864062014805 |
[1,0,5,0,21,0,85,0,341,0,1365,0,5461,0,21845,0, 87381,0,349525,0,1398101,0,5592405,0,22369621,0, 89478485,0,357913941,0,1431655765,0,5726623061,0, 22906492245,0,91625968981,0,366503875925,0, 1466015503701,0,5864062014805] |