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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 6 |
| 3 | 49 |
| 4 | 961 |
| 5 | 8214 |
| 6 | 70225 |
| 7 | 1385329 |
| 8 | 11844150 |
| 9 | 101263969 |
| 10 | 1997643025 |
| 11 | 17079255654 |
| 12 | 146022572641 |
| 13 | 2880599856289 |
| 14 | 24628274808486 |
| 15 | 210564448483921 |
| 16 | 4153822995125281 |
| 17 | 35513955194580726 |
| 18 | 303633788691241009 |
| 19 | 5989809878370798481 |
| 20 | 51211098762310597974 |
[1,6,49,961,8214,70225,1385329,11844150,101263969, 1997643025,17079255654,146022572641,2880599856289, 24628274808486,210564448483921,4153822995125281, 35513955194580726,303633788691241009, 5989809878370798481,51211098762310597974] |