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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 6 |
| 5 | 60 |
| 6 | 360 |
| 7 | 70 |
| 8 | 336 |
| 9 | 756 |
| 10 | 75600 |
| 11 | 207900 |
| 12 | 9979200 |
| 13 | 25945920 |
| 14 | 1816214400 |
| 15 | 3405402000 |
| 16 | 504504000 |
| 17 | 308756448000 |
| 18 | 505237824000 |
| 19 | 52797352608000 |
| 20 | 1055947052160000 |
| 21 | 221748880953600 |
| 22 | 12196188452448000 |
| 23 | 280512334406304000 |
| 24 | 2692918410300518400 |
| 25 | 106557391987200000 |
| 26 | 972442759275187200000 |
[1,1,2,3,6,60,360,70,336,756,75600,207900,9979200, 25945920,1816214400,3405402000,504504000, 308756448000,505237824000,52797352608000, 1055947052160000,221748880953600, 12196188452448000,280512334406304000, 2692918410300518400,106557391987200000, 972442759275187200000] |