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| n | a(n) |
|---|---|
| 1 | 9 |
| 2 | 69 |
| 3 | 613 |
| 4 | 4361 |
| 5 | 35067 |
| 6 | 271863 |
| 7 | 2122623 |
| 8 | 16577231 |
| 9 | 129398981 |
| 10 | 1010161409 |
| 11 | 7886865189 |
| 12 | 61570433261 |
| 13 | 480690831603 |
| 14 | 3752745812035 |
| 15 | 29297882184787 |
| 16 | 228729463311571 |
| 17 | 1785699822954649 |
| 18 | 13941021624348057 |
| 19 | 108838075075791297 |
[9,69,613,4361,35067,271863,2122623,16577231, 129398981,1010161409,7886865189,61570433261, 480690831603,3752745812035,29297882184787, 228729463311571,1785699822954649, 13941021624348057,108838075075791297] |