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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 7 |
| 3 | 1172 |
| 4 | 36325278240 |
| 5 | 18272974787063551687986348306336 |
| 6 | 244766458691906180755079840538506099505695351680436638205950721844523539763881615360 |
[2,7,1172,36325278240, 18272974787063551687986348306336, 24476645869190618075507984053850609950569535168043\ 6638205950721844523539763881615360] |