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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 7 |
| 3 | 19 |
| 4 | 55 |
| 5 | 139 |
| 6 | 859 |
| 7 | 2119 |
| 8 | 112999 |
| 9 | 333679 |
| 10 | 10040119 |
| 11 | 15363619 |
| 12 | 548687179 |
| 13 | 16632374359 |
| 14 | 5733638351299 |
| 15 | 14360489685499 |
| 16 | 433098704482699 |
| 17 | 44258681327079259 |
| 18 | 5009018648920510999 |
[3,7,19,55,139,859,2119,112999,333679,10040119, 15363619,548687179,16632374359,5733638351299, 14360489685499,433098704482699,44258681327079259, 5009018648920510999] |