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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 2 |
| 3 | 4 |
| 4 | 10 |
| 5 | 102 |
| 6 | 9988 |
| 7 | 462079550 |
| 8 | 1246459580018549814 |
| 9 | 3451767175159069042246539740614797183 |
| 10 | 16047263805335625632784779620610026996218698731392917143951229224582015756 |
[2,2,4,10,102,9988,462079550,1246459580018549814, 3451767175159069042246539740614797183, 16047263805335625632784779620610026996218698731392\ 917143951229224582015756] |