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| n | a(n) |
|---|---|
| 1 | 192 |
| 2 | 1152 |
| 3 | 20160 |
| 4 | 103680 |
| 5 | 806400 |
| 6 | 3104640 |
| 7 | 12945600 |
| 8 | 26853120 |
| 9 | 108201600 |
| 10 | 136002240 |
| 11 | 362597760 |
| 12 | 506160000 |
| 13 | 1049630400 |
| 14 | 1358807040 |
| 15 | 1536796800 |
| 16 | 2702128320 |
| 17 | 3317529600 |
| 18 | 5314118400 |
| 19 | 6323748480 |
| 20 | 9475464960 |
| 21 | 14665694400 |
[192,1152,20160,103680,806400,3104640,12945600, 26853120,108201600,136002240,362597760,506160000, 1049630400,1358807040,1536796800,2702128320, 3317529600,5314118400,6323748480,9475464960, 14665694400] |