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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 56 |
| 3 | 555 |
| 4 | 11200 |
| 5 | 112723 |
| 6 | 1231014 |
| 7 | 18047775 |
| 8 | 249080912 |
| 9 | 3224160693 |
| 10 | 42170084169 |
| 11 | 562089504718 |
| 12 | 7496675641466 |
| 13 | 99355372063480 |
| 14 | 1315111559086294 |
| 15 | 17446330077786508 |
| 16 | 231599788865925152 |
| 17 | 3072162248942709113 |
[2,56,555,11200,112723,1231014,18047775,249080912, 3224160693,42170084169,562089504718,7496675641466, 99355372063480,1315111559086294,17446330077786508, 231599788865925152,3072162248942709113] |