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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 3 |
| 3 | 7 |
| 4 | 23 |
| 5 | 29 |
| 6 | 157 |
| 7 | 907 |
| 8 | 1669 |
| 9 | 1879 |
| 10 | 2089 |
| 11 | 60881279 |
| 12 | 147692870693 |
| 13 | 15293983 |
| 14 | 834172688773 |
| 15 | 894476586329191 |
| 16 | 1275290173878841 |
| 17 | 259268969935081 |
| 18 | 1027994118842320951 |
| 19 | 1424014323186726053 |
| 20 | 1424014323196425743 |
| 21 | 28112131522925191409 |
[2,3,7,23,29,157,907,1669,1879,2089,60881279, 147692870693,15293983,834172688773, 894476586329191,1275290173878841,259268969935081, 1027994118842320951,1424014323186726053, 1424014323196425743,28112131522925191409] |