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| n | a(n) |
|---|---|
| 1 | 6 |
| 2 | 27 |
| 3 | 167 |
| 4 | 1206 |
| 5 | 9442 |
| 6 | 77563 |
| 7 | 658097 |
| 8 | 5714972 |
| 9 | 50503822 |
| 10 | 452425909 |
| 11 | 4097411586 |
| 12 | 37441633014 |
| 13 | 344698955565 |
| 14 | 3193520274110 |
| 15 | 29747746198318 |
| 16 | 278407464679282 |
| 17 | 2616351626277085 |
| 18 | 24676888631241563 |
| 19 | 233501199663256017 |
| 20 | 2215874110986269907 |
[6,27,167,1206,9442,77563,658097,5714972,50503822, 452425909,4097411586,37441633014,344698955565, 3193520274110,29747746198318,278407464679282, 2616351626277085,24676888631241563, 233501199663256017,2215874110986269907] |