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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 12 |
| 3 | 270 |
| 4 | 16640 |
| 5 | 48831250 |
| 6 | 13060740672 |
| 7 | 232630514810750 |
| 8 | 144115188092633088 |
| 9 | 8862938119652888516418 |
| 10 | 100000000000000000010000000000 |
| 11 | 191943424957750480504432152962422 |
| 12 | 8505622499821102144576131693030930382848 |
| 13 | 4695452425098908797088971409337724910182721066 |
[2,12,270,16640,48831250,13060740672, 232630514810750,144115188092633088, 8862938119652888516418, 100000000000000000010000000000, 191943424957750480504432152962422, 8505622499821102144576131693030930382848, 4695452425098908797088971409337724910182721066] |