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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 13 |
| 5 | 77 |
| 6 | 1494 |
| 7 | 56978 |
| 8 | 4495023 |
| 9 | 669203528 |
| 10 | 187623057932 |
| 11 | 98793520541768 |
| 12 | 97702673827558670 |
[1,2,3,13,77,1494,56978,4495023,669203528, 187623057932,98793520541768,97702673827558670] |