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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 6 |
| 3 | 86 |
| 4 | 7626 |
| 5 | 3956996 |
| 6 | 8326366368 |
| 7 | 69277957195904 |
| 8 | 2287898999182608384 |
| 9 | 301053169143557925650432 |
| 10 | 158147142250171927345054089216 |
| 11 | 331982638848895606930198405868158976 |
| 12 | 2786232352655643085145552249123037486514176 |
[1,2,6,86,7626,3956996,8326366368,69277957195904, 2287898999182608384,301053169143557925650432, 158147142250171927345054089216, 331982638848895606930198405868158976, 2786232352655643085145552249123037486514176] |