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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 12 |
| 2 | 160 |
| 3 | 2520 |
| 4 | 46480 |
| 5 | 987840 |
| 6 | 23826880 |
| 7 | 643843200 |
| 8 | 19280060800 |
| 9 | 634002969600 |
| 10 | 22718375680000 |
| 11 | 881259515136000 |
| 12 | 36796205974528000 |
| 13 | 1645615697037312000 |
| 14 | 78486991029551104000 |
| 15 | 3976930001842237440000 |
| 16 | 213353732165508014080000 |
| 17 | 12081783988797659136000000 |
[1,12,160,2520,46480,987840,23826880,643843200, 19280060800,634002969600,22718375680000, 881259515136000,36796205974528000, 1645615697037312000,78486991029551104000, 3976930001842237440000,213353732165508014080000, 12081783988797659136000000] |