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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 7 |
| 3 | 47 |
| 4 | 127 |
| 5 | 1087 |
| 6 | 2207 |
| 7 | 4481 |
| 8 | 21503 |
| 9 | 34303 |
| 10 | 119809 |
| 11 | 524287 |
| 12 | 65241089 |
| 13 | 167772161 |
| 14 | 1811939329 |
| 15 | 2147483647 |
| 16 | 3758096383 |
| 17 | 16074670081 |
| 18 | 73327699969 |
| 19 | 186812208641 |
| 20 | 206158430209 |
| 21 | 2142130536449 |
| 22 | 2878401282049 |
| 23 | 5703716569087 |
| 24 | 15868293545983 |
| 25 | 274367023939583 |
[3,7,47,127,1087,2207,4481,21503,34303,119809, 524287,65241089,167772161,1811939329,2147483647, 3758096383,16074670081,73327699969,186812208641, 206158430209,2142130536449,2878401282049, 5703716569087,15868293545983,274367023939583] |