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| n | a(n) |
|---|---|
| 1 | 9 |
| 2 | 81 |
| 3 | 369 |
| 4 | 2241 |
| 5 | 12609 |
| 6 | 73089 |
| 7 | 419841 |
| 8 | 2419713 |
| 9 | 13930497 |
| 10 | 80230401 |
| 11 | 462012417 |
| 12 | 2660655105 |
| 13 | 15322038273 |
| 14 | 88236228609 |
| 15 | 508131934209 |
| 16 | 2926215692289 |
| 17 | 16851403538433 |
| 18 | 97043367329793 |
| 19 | 558850475294721 |
| 20 | 3218291629752321 |
[9,81,369,2241,12609,73089,419841,2419713, 13930497,80230401,462012417,2660655105, 15322038273,88236228609,508131934209, 2926215692289,16851403538433,97043367329793, 558850475294721,3218291629752321] |