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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 3 |
| 3 | 5 |
| 4 | 6 |
| 5 | 52 |
| 6 | 668 |
| 7 | 171510 |
| 8 | 4590170768 |
| 9 | 17103459833953822083 |
| 10 | 31906466290986600582512428032058109695 |
| 11 | 237271596693541800921324673318278335675822001026279366213434934428597656224 |
[2,3,5,6,52,668,171510,4590170768, 17103459833953822083, 31906466290986600582512428032058109695, 23727159669354180092132467331827833567582200102627\ 9366213434934428597656224] |