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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 7 |
| 3 | 49 |
| 4 | 421 |
| 5 | 3697 |
| 6 | 37933 |
| 7 | 404341 |
| 8 | 4841341 |
| 9 | 61291861 |
| 10 | 848268421 |
| 11 | 12465197269 |
| 12 | 197121724549 |
| 13 | 3302727019621 |
| 14 | 58876330343173 |
| 15 | 1107627703783909 |
| 16 | 21990846791015845 |
| 17 | 458649487144877029 |
| 18 | 10035575758396240549 |
| 19 | 229687317927141716005 |
| 20 | 5489966024995169233573 |
[1,7,49,421,3697,37933,404341,4841341,61291861, 848268421,12465197269,197121724549,3302727019621, 58876330343173,1107627703783909,21990846791015845, 458649487144877029,10035575758396240549, 229687317927141716005,5489966024995169233573] |