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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 24 |
| 5 | 120 |
| 6 | 720 |
| 7 | 5040 |
| 8 | 40320 |
| 9 | 362878 |
| 10 | 3627778 |
| 11 | 39830282 |
| 12 | 475089392 |
| 13 | 6094561180 |
| 14 | 83333937940 |
| 15 | 1205398303180 |
| 16 | 18331873363480 |
| 17 | 291706615484450 |
| 18 | 4838414115229430 |
| 19 | 83404373736108502 |
| 20 | 1490681666580459304 |
| 21 | 27572241018065482032 |
| 22 | 526959942343051879032 |
[1,1,2,6,24,120,720,5040,40320,362878,3627778, 39830282,475089392,6094561180,83333937940, 1205398303180,18331873363480,291706615484450, 4838414115229430,83404373736108502, 1490681666580459304,27572241018065482032, 526959942343051879032] |