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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 7 |
| 3 | 28 |
| 4 | 231 |
| 5 | 3022 |
| 6 | 63851 |
| 7 | 2254102 |
| 8 | 129926375 |
| 9 | 12346854981 |
| 10 | 1930513304865 |
| 11 | 496013097993148 |
| 12 | 209682700667891310 |
| 13 | 145774046555290357339 |
| 14 | 166670977286765976049136 |
| 15 | 313418443881609705847873703 |
[2,7,28,231,3022,63851,2254102,129926375, 12346854981,1930513304865,496013097993148, 209682700667891310,145774046555290357339, 166670977286765976049136, 313418443881609705847873703] |