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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 9 |
| 3 | 58 |
| 4 | 475 |
| 5 | 4666 |
| 6 | 53116 |
| 7 | 684762 |
| 8 | 9833391 |
| 9 | 155341258 |
| 10 | 2673209561 |
| 11 | 49717424868 |
| 12 | 992847765988 |
| 13 | 21172798741316 |
| 14 | 479921234767976 |
| 15 | 11516219861132586 |
| 16 | 291523666535143823 |
| 17 | 7761036379846481206 |
| 18 | 216699016885046232187 |
| 19 | 6330257697841339549706 |
| 20 | 193043926318644060255531 |
[1,2,9,58,475,4666,53116,684762,9833391,155341258, 2673209561,49717424868,992847765988, 21172798741316,479921234767976,11516219861132586, 291523666535143823,7761036379846481206, 216699016885046232187,6330257697841339549706, 193043926318644060255531] |