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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 8 |
| 3 | 15 |
| 4 | 48 |
| 5 | 1152 |
| 6 | 19200 |
| 7 | 62370 |
| 8 | 322560 |
| 9 | 17418240 |
| 10 | 567705600 |
| 11 | 2481078600 |
| 12 | 16907304960 |
| 13 | 1504935936000 |
| 14 | 8799558768000 |
| 15 | 76435881984000 |
| 16 | 819678899239200 |
| 17 | 10176845001523200 |
| 18 | 2169274855587840000 |
| 19 | 215013524533936128000 |
[2,8,15,48,1152,19200,62370,322560,17418240, 567705600,2481078600,16907304960,1504935936000, 8799558768000,76435881984000,819678899239200, 10176845001523200,2169274855587840000, 215013524533936128000] |