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| n | a(n) |
|---|---|
| 6 | 720 |
| 7 | 2520 |
| 8 | 16800 |
| 9 | 90720 |
| 10 | 584640 |
| 11 | 3548160 |
| 12 | 25098480 |
| 13 | 125456760 |
| 14 | 778065288 |
| 15 | 4353689340 |
| 16 | 26986202880 |
| 17 | 151871712720 |
| 18 | 970831418976 |
| 19 | 5215235977368 |
| 20 | 31594145929440 |
| 21 | 180858169411920 |
| 22 | 1087286184860568 |
| 23 | 6173944667695728 |
| 24 | 38303414229539712 |
| 25 | 212004108343328400 |
[720,2520,16800,90720,584640,3548160,25098480, 125456760,778065288,4353689340,26986202880, 151871712720,970831418976,5215235977368, 31594145929440,180858169411920,1087286184860568, 6173944667695728,38303414229539712, 212004108343328400] |