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| n | a(n) |
|---|---|
| 1 | 13 |
| 2 | 127 |
| 3 | 967 |
| 4 | 7581 |
| 5 | 59533 |
| 6 | 468159 |
| 7 | 3681179 |
| 8 | 28943479 |
| 9 | 227567727 |
| 10 | 1789258703 |
| 11 | 14068129953 |
| 12 | 110611309721 |
| 13 | 869686276975 |
| 14 | 6837946387417 |
| 15 | 53763653212357 |
| 16 | 422719081839837 |
| 17 | 3323647323173331 |
| 18 | 26132322856122051 |
| 19 | 205466534630289505 |
[13,127,967,7581,59533,468159,3681179,28943479, 227567727,1789258703,14068129953,110611309721, 869686276975,6837946387417,53763653212357, 422719081839837,3323647323173331, 26132322856122051,205466534630289505] |