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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 8 |
| 3 | 24 |
| 4 | 24 |
| 5 | 1920 |
| 6 | 7680 |
| 7 | 322560 |
| 8 | 64 |
| 9 | 92897280 |
| 10 | 3715891200 |
| 11 | 40874803200 |
| 12 | 194641920 |
| 13 | 25505877196800 |
| 14 | 1428329123020800 |
| 15 | 21424936845312000 |
| 16 | 160 |
| 17 | 23310331287699456000 |
| 18 | 1678343852714360832000 |
| 19 | 31888533201572855808000 |
[2,8,24,24,1920,7680,322560,64,92897280, 3715891200,40874803200,194641920,25505877196800, 1428329123020800,21424936845312000,160, 23310331287699456000,1678343852714360832000, 31888533201572855808000] |