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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 0 |
| 7 | 0 |
| 8 | 0 |
| 9 | 40320 |
| 10 | 403200 |
| 11 | 4435200 |
| 12 | 53222400 |
| 13 | 691891200 |
| 14 | 9686476800 |
| 15 | 145297152000 |
| 16 | 2324754432000 |
| 17 | 39520825344000 |
| 18 | 671854030848000 |
| 19 | 12765226586112000 |
| 20 | 255304531722240000 |
| 21 | 5361395166167040000 |
| 22 | 117950693655674880000 |
| 23 | 2712865954080522240000 |
[0,0,0,0,0,0,0,0,0,40320,403200,4435200,53222400, 691891200,9686476800,145297152000,2324754432000, 39520825344000,671854030848000,12765226586112000, 255304531722240000,5361395166167040000, 117950693655674880000,2712865954080522240000] |