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| n | a(n) |
|---|---|
| 2 | 6 |
| 3 | 480 |
| 4 | 197820 |
| 5 | 150474240 |
| 6 | 208857587400 |
| 7 | 471804812519040 |
| 8 | 1625459273858019600 |
| 9 | 8112729590064978278400 |
| 10 | 56342429224416522460072800 |
| 11 | 527075322501595757416502976000 |
| 12 | 6466573585901882433727764077860800 |
| 13 | 101749747195531624711768653503416320000 |
[6,480,197820,150474240,208857587400, 471804812519040,1625459273858019600, 8112729590064978278400,56342429224416522460072800, 527075322501595757416502976000, 6466573585901882433727764077860800, 101749747195531624711768653503416320000] |