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| n | a(n) |
|---|---|
| 2 | 4 |
| 3 | 16 |
| 4 | 25 |
| 5 | 57 |
| 6 | 129 |
| 7 | 289 |
| 8 | 641 |
| 9 | 1409 |
| 10 | 3073 |
| 11 | 6657 |
| 12 | 14337 |
| 13 | 30721 |
| 14 | 65537 |
| 15 | 139265 |
| 16 | 294913 |
| 17 | 622593 |
| 18 | 1310721 |
| 19 | 2752513 |
| 20 | 5767169 |
| 21 | 12058625 |
| 22 | 25165825 |
| 23 | 52428801 |
| 24 | 109051905 |
| 25 | 226492417 |
| 26 | 469762049 |
| 27 | 973078529 |
| 28 | 2013265921 |
| 29 | 4160749569 |
| 30 | 8589934593 |
| 31 | 17716740097 |
| 32 | 36507222017 |
[4,16,25,57,129,289,641,1409,3073,6657,14337, 30721,65537,139265,294913,622593,1310721,2752513, 5767169,12058625,25165825,52428801,109051905, 226492417,469762049,973078529,2013265921, 4160749569,8589934593,17716740097,36507222017] |