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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 12 |
| 4 | 200 |
| 5 | 4034 |
| 6 | 92752 |
| 7 | 2353272 |
| 8 | 64579809 |
| 9 | 1891598860 |
| 10 | 58591554652 |
| 11 | 1906271367296 |
| 12 | 64816527248936 |
| 13 | 2294331974613872 |
| 14 | 84290267670946720 |
| 15 | 3206227129084419920 |
| 16 | 126022120854865417140 |
| 17 | 5110001578581607976400 |
| 18 | 213458728365617240931360 |
| 19 | 9175021814527973211291880 |
| 20 | 405366362599820848509766760 |
| 21 | 18392202994173383123235536800 |
| 22 | 856255190568423353781484124240 |
[1,1,12,200,4034,92752,2353272,64579809, 1891598860,58591554652,1906271367296, 64816527248936,2294331974613872,84290267670946720, 3206227129084419920,126022120854865417140, 5110001578581607976400,213458728365617240931360, 9175021814527973211291880, 405366362599820848509766760, 18392202994173383123235536800, 856255190568423353781484124240] |