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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 7 |
| 3 | 45 |
| 4 | 391 |
| 5 | 4376 |
| 6 | 60864 |
| 7 | 1012186 |
| 8 | 19622935 |
| 9 | 434351705 |
| 10 | 10807060863 |
| 11 | 298525056829 |
| 12 | 9063891473730 |
| 13 | 300004447041493 |
| 14 | 10750198453038838 |
| 15 | 414596707456493479 |
| 16 | 17122019740329088733 |
| 17 | 753855850836114017867 |
| 18 | 35248703133243910547502 |
[2,7,45,391,4376,60864,1012186,19622935,434351705, 10807060863,298525056829,9063891473730, 300004447041493,10750198453038838, 414596707456493479,17122019740329088733, 753855850836114017867,35248703133243910547502] |