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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 43 |
| 3 | 41 |
| 4 | 139 |
| 5 | 269 |
| 6 | 773 |
| 7 | 1049 |
| 8 | 2309 |
| 9 | 4357 |
| 10 | 8737 |
| 11 | 16673 |
| 12 | 34819 |
| 13 | 66569 |
| 14 | 139393 |
| 15 | 279553 |
| 16 | 589829 |
| 17 | 1051649 |
| 18 | 2621569 |
| 19 | 4260097 |
| 20 | 9437189 |
| 21 | 17039489 |
| 22 | 33817601 |
| 23 | 67649537 |
| 24 | 167903233 |
| 25 | 269484097 |
| 26 | 545260033 |
| 27 | 1074267137 |
| 28 | 2155872769 |
| 29 | 4311760897 |
| 30 | 12884901893 |
| 31 | 17184063521 |
[2,43,41,139,269,773,1049,2309,4357,8737,16673, 34819,66569,139393,279553,589829,1051649,2621569, 4260097,9437189,17039489,33817601,67649537, 167903233,269484097,545260033,1074267137, 2155872769,4311760897,12884901893,17184063521] |