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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 2 |
| 2 | 8 |
| 3 | 168 |
| 4 | 5760 |
| 5 | 310304 |
| 6 | 23894144 |
| 7 | 2481859968 |
| 8 | 333725331456 |
| 9 | 56329065984512 |
| 10 | 11650274400684032 |
| 11 | 2895770490247219200 |
| 12 | 851263005980215443456 |
| 13 | 292012329049579197046784 |
| 14 | 115560631410392130840461312 |
| 15 | 52240866338892496235877335040 |
[0,2,8,168,5760,310304,23894144,2481859968, 333725331456,56329065984512,11650274400684032, 2895770490247219200,851263005980215443456, 292012329049579197046784, 115560631410392130840461312, 52240866338892496235877335040] |