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| n | a(n) |
|---|---|
| 1 | 12 |
| 2 | 288 |
| 3 | 5544 |
| 4 | 57408 |
| 5 | 458400 |
| 6 | 3339648 |
| 7 | 21641088 |
| 8 | 133367808 |
| 9 | 770867712 |
| 10 | 4318341120 |
| 11 | 23246936064 |
| 12 | 122502168576 |
| 13 | 628395515904 |
| 14 | 3173912641536 |
| 15 | 15723815731200 |
| 16 | 76986895564800 |
| 17 | 371499757338624 |
| 18 | 1776217326354432 |
| 19 | 8396759769808896 |
| 20 | 39400619366154240 |
[12,288,5544,57408,458400,3339648,21641088, 133367808,770867712,4318341120,23246936064, 122502168576,628395515904,3173912641536, 15723815731200,76986895564800,371499757338624, 1776217326354432,8396759769808896, 39400619366154240] |