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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 7 |
| 3 | 21 |
| 4 | 31 |
| 5 | 81 |
| 6 | 93 |
| 7 | 127 |
| 8 | 217 |
| 9 | 381 |
| 10 | 400 |
| 11 | 651 |
| 12 | 889 |
| 13 | 2667 |
| 14 | 3937 |
| 15 | 8191 |
| 16 | 11811 |
| 17 | 24573 |
| 18 | 27559 |
| 19 | 57337 |
| 20 | 82677 |
| 21 | 131071 |
| 22 | 172011 |
| 23 | 253921 |
| 24 | 393213 |
| 25 | 524287 |
| 26 | 761763 |
| 27 | 917497 |
| 28 | 1040257 |
| 29 | 1572861 |
| 30 | 1777447 |
| 31 | 2752491 |
| 32 | 3120771 |
| 33 | 3670009 |
| 34 | 4063201 |
| 35 | 5332341 |
[3,7,21,31,81,93,127,217,381,400,651,889,2667, 3937,8191,11811,24573,27559,57337,82677,131071, 172011,253921,393213,524287,761763,917497,1040257, 1572861,1777447,2752491,3120771,3670009,4063201, 5332341] |