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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 12 |
| 3 | 216 |
| 4 | 8640 |
| 5 | 933120 |
| 6 | 209018880 |
| 7 | 100329062400 |
| 8 | 130026464870400 |
| 9 | 349511137571635200 |
| 10 | 1968446726803449446400 |
| 11 | 22676506292775737622528000 |
| 12 | 522466704985552994823045120000 |
| 13 | 27820307107070725868337506549760000 |
[2,12,216,8640,933120,209018880,100329062400, 130026464870400,349511137571635200, 1968446726803449446400,22676506292775737622528000, 522466704985552994823045120000, 27820307107070725868337506549760000] |