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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 7 |
| 3 | 74 |
| 4 | 1596 |
| 5 | 58344 |
| 6 | 3240840 |
| 7 | 254535840 |
| 8 | 26862378480 |
| 9 | 3667537480320 |
| 10 | 629083000385280 |
| 11 | 132437508454137600 |
| 12 | 33575888768939193600 |
| 13 | 10090248381797704243200 |
| 14 | 3546915020658948703564800 |
| 15 | 1441883923593020355819571200 |
| 16 | 671220876625092844683849216000 |
| 17 | 354750674999711346878469083136000 |
[1,2,7,74,1596,58344,3240840,254535840, 26862378480,3667537480320,629083000385280, 132437508454137600,33575888768939193600, 10090248381797704243200,3546915020658948703564800, 1441883923593020355819571200, 671220876625092844683849216000, 354750674999711346878469083136000] |