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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 9 |
| 4 | 69 |
| 5 | 623 |
| 6 | 7793 |
| 7 | 110430 |
| 8 | 1906317 |
| 9 | 36833614 |
| 10 | 816101825 |
| 11 | 19925210834 |
| 12 | 541363267613 |
| 13 | 15997458049946 |
| 14 | 515769374925576 |
| 15 | 17905023985615254 |
| 16 | 669030297769291562 |
| 17 | 26689471638523499483 |
| 18 | 1134895275721374771655 |
| 19 | 51161002326406795249910 |
| 20 | 2440166138715867838359915 |
[1,2,9,69,623,7793,110430,1906317,36833614, 816101825,19925210834,541363267613,15997458049946, 515769374925576,17905023985615254, 669030297769291562,26689471638523499483, 1134895275721374771655,51161002326406795249910, 2440166138715867838359915] |