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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 8 |
| 3 | 332 |
| 4 | 3750 |
| 5 | 68591 |
| 6 | 899432 |
| 7 | 13506023 |
| 8 | 180160012 |
| 9 | 2510785227 |
| 10 | 33330848454 |
| 11 | 448079715759 |
| 12 | 5893418278271 |
| 13 | 77649390052196 |
| 14 | 1011970457365017 |
| 15 | 13165754032331389 |
| 16 | 170232985496817728 |
| 17 | 2195480228590892060 |
| 18 | 28203099820000893198 |
| 19 | 361391865363036263917 |
[1,8,332,3750,68591,899432,13506023,180160012, 2510785227,33330848454,448079715759,5893418278271, 77649390052196,1011970457365017,13165754032331389, 170232985496817728,2195480228590892060, 28203099820000893198,361391865363036263917] |