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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 3 |
| 3 | 5 |
| 4 | 7 |
| 5 | 13 |
| 6 | 37 |
| 7 | 61 |
| 8 | 181 |
| 9 | 241 |
| 10 | 2521 |
| 11 | 7561 |
| 12 | 15121 |
| 13 | 20161 |
| 14 | 45361 |
| 15 | 55441 |
| 16 | 110881 |
| 17 | 332641 |
| 18 | 498961 |
| 19 | 4324321 |
| 20 | 14414401 |
| 21 | 43243201 |
| 22 | 110270161 |
| 23 | 183783601 |
| 24 | 367567201 |
| 25 | 4655851201 |
| 26 | 13967553601 |
| 27 | 73329656401 |
| 28 | 293318625601 |
| 29 | 1606268664001 |
[2,3,5,7,13,37,61,181,241,2521,7561,15121,20161, 45361,55441,110881,332641,498961,4324321,14414401, 43243201,110270161,183783601,367567201,4655851201, 13967553601,73329656401,293318625601, 1606268664001] |