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| n | a(n) |
|---|---|
| 1 | 7 |
| 2 | 63 |
| 3 | 511 |
| 4 | 4091 |
| 5 | 32739 |
| 6 | 261905 |
| 7 | 2095233 |
| 8 | 16761837 |
| 9 | 134094563 |
| 10 | 1072755573 |
| 11 | 8582037499 |
| 12 | 68656243311 |
| 13 | 549249492763 |
| 14 | 4393992312383 |
| 15 | 35151909460619 |
| 16 | 281215043377605 |
| 17 | 2249718488563135 |
| 18 | 17997733040855701 |
| 19 | 143981745385748627 |
[7,63,511,4091,32739,261905,2095233,16761837, 134094563,1072755573,8582037499,68656243311, 549249492763,4393992312383,35151909460619, 281215043377605,2249718488563135, 17997733040855701,143981745385748627] |