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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 11 |
| 4 | 43 |
| 5 | 85 |
| 6 | 341 |
| 7 | 683 |
| 8 | 2731 |
| 9 | 5461 |
| 10 | 21845 |
| 11 | 43691 |
| 12 | 174763 |
| 13 | 349525 |
| 14 | 1398101 |
| 15 | 2796203 |
| 16 | 11184811 |
| 17 | 22369621 |
| 18 | 89478485 |
| 19 | 178956971 |
| 20 | 715827883 |
| 21 | 1431655765 |
| 22 | 5726623061 |
| 23 | 11453246123 |
| 24 | 45812984491 |
| 25 | 91625968981 |
| 26 | 366503875925 |
| 27 | 733007751851 |
[1,1,5,11,43,85,341,683,2731,5461,21845,43691, 174763,349525,1398101,2796203,11184811,22369621, 89478485,178956971,715827883,1431655765, 5726623061,11453246123,45812984491,91625968981, 366503875925,733007751851] |