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| n | a(n) |
|---|---|
| 0 | 9 |
| 1 | 29 |
| 2 | 89 |
| 3 | 269 |
| 4 | 809 |
| 5 | 2429 |
| 6 | 7289 |
| 7 | 21869 |
| 8 | 65609 |
| 9 | 196829 |
| 10 | 590489 |
| 11 | 1771469 |
| 12 | 5314409 |
| 13 | 15943229 |
| 14 | 47829689 |
| 15 | 143489069 |
| 16 | 430467209 |
| 17 | 1291401629 |
| 18 | 3874204889 |
| 19 | 11622614669 |
| 20 | 34867844009 |
| 21 | 104603532029 |
| 22 | 313810596089 |
| 23 | 941431788269 |
| 24 | 2824295364809 |
[9,29,89,269,809,2429,7289,21869,65609,196829, 590489,1771469,5314409,15943229,47829689, 143489069,430467209,1291401629,3874204889, 11622614669,34867844009,104603532029,313810596089, 941431788269,2824295364809] |