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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 7 |
| 3 | 23 |
| 4 | 41 |
| 5 | 109 |
| 6 | 457 |
| 7 | 2137 |
| 8 | 14293 |
| 9 | 55441 |
| 10 | 57991 |
| 11 | 221101 |
| 12 | 513991 |
| 13 | 2447761 |
| 14 | 3248701 |
| 15 | 4076641 |
| 16 | 11643607 |
| 17 | 16135981 |
| 18 | 25400761 |
| 19 | 25738831 |
| 20 | 399263281 |
| 21 | 741488749 |
| 22 | 794932741 |
| 23 | 5516118301 |
| 24 | 9237839521 |
| 25 | 10453202761 |
| 26 | 20833333501 |
[3,7,23,41,109,457,2137,14293,55441,57991,221101, 513991,2447761,3248701,4076641,11643607,16135981, 25400761,25738831,399263281,741488749,794932741, 5516118301,9237839521,10453202761,20833333501] |