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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 72 |
| 2 | 22920 |
| 3 | 9314448 |
| 4 | 4211047080 |
| 5 | 2021601931776 |
| 6 | 1008673456254640 |
| 7 | 516987835463640000 |
| 8 | 270280816277448460968 |
| 9 | 143468491665604992744000 |
| 10 | 77077894838606703430234560 |
| 11 | 41816670323883372478262418912 |
| 12 | 22870956616373890690700028823920 |
[1,72,22920,9314448,4211047080,2021601931776, 1008673456254640,516987835463640000, 270280816277448460968,143468491665604992744000, 77077894838606703430234560, 41816670323883372478262418912, 22870956616373890690700028823920] |