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| n | a(n) |
|---|---|
| 0 | 31 |
| 1 | 8 |
| 2 | 4104 |
| 3 | 157472 |
| 4 | 2093064 |
| 5 | 15625008 |
| 6 | 80783136 |
| 7 | 322828864 |
| 8 | 1071640584 |
| 9 | 3099521384 |
| 10 | 8015629104 |
| 11 | 18863581536 |
| 12 | 41199871776 |
| 13 | 84835994992 |
| 14 | 165611207232 |
| 15 | 307562657472 |
| 16 | 548679970824 |
| 17 | 948703011984 |
| 18 | 1590054469992 |
| 19 | 2581501582240 |
[31,8,4104,157472,2093064,15625008,80783136, 322828864,1071640584,3099521384,8015629104, 18863581536,41199871776,84835994992,165611207232, 307562657472,548679970824,948703011984, 1590054469992,2581501582240] |