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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 12 |
| 2 | 240 |
| 3 | 5376 |
| 4 | 126720 |
| 5 | 3075072 |
| 6 | 76038144 |
| 7 | 1905131520 |
| 8 | 48199827456 |
| 9 | 1228623052800 |
| 10 | 31504481648640 |
| 11 | 811751838842880 |
| 12 | 20999667135283200 |
| 13 | 545086744471535616 |
| 14 | 14189559697354260480 |
| 15 | 370298578584748425216 |
| 16 | 9684502341534993088512 |
| 17 | 253765034617761850982400 |
[1,12,240,5376,126720,3075072,76038144,1905131520, 48199827456,1228623052800,31504481648640, 811751838842880,20999667135283200, 545086744471535616,14189559697354260480, 370298578584748425216,9684502341534993088512, 253765034617761850982400] |