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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 15 |
| 4 | 105 |
| 5 | 2415 |
| 6 | 26565 |
| 7 | 1567335 |
| 8 | 2785154295 |
| 9 | 6918860803558935 |
| 10 | 24055444284403886996443725 |
| 11 | 332872543972802173225078010738842685950725 |
| 12 | 571002075998998180604720399522520480910497598676930064638396594614026468525 |
[1,3,15,105,2415,26565,1567335,2785154295, 6918860803558935,24055444284403886996443725, 332872543972802173225078010738842685950725, 57100207599899818060472039952252048091049759867693\ 0064638396594614026468525] |