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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 12 |
| 4 | 48 |
| 5 | 540 |
| 6 | 5040 |
| 7 | 53760 |
| 8 | 745920 |
| 9 | 12897360 |
| 10 | 206236800 |
| 11 | 3682657440 |
| 12 | 83366236800 |
| 13 | 1849952744640 |
| 14 | 45496897205760 |
| 15 | 1176291493977600 |
| 16 | 32097739145472000 |
| 17 | 983522184476832000 |
| 18 | 31186123650255974400 |
| 19 | 1021800029809932172800 |
| 20 | 35859334900163943168000 |
| 21 | 1320567044275182140236800 |
| 22 | 50849016060752080883712000 |
| 23 | 2063131407115000462188748800 |
| 24 | 86946484539570696351914803200 |
[1,2,12,48,540,5040,53760,745920,12897360, 206236800,3682657440,83366236800,1849952744640, 45496897205760,1176291493977600,32097739145472000, 983522184476832000,31186123650255974400, 1021800029809932172800,35859334900163943168000, 1320567044275182140236800, 50849016060752080883712000, 2063131407115000462188748800, 86946484539570696351914803200] |