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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 1 |
| 4 | 3 |
| 5 | 6 |
| 6 | 35 |
| 7 | 120 |
| 8 | 105 |
| 9 | 1120 |
| 10 | 19089 |
| 11 | 362880 |
| 12 | 133595 |
| 13 | 39916800 |
| 14 | 148397535 |
| 15 | 458313856 |
| 16 | 2027025 |
| 17 | 1307674368000 |
| 18 | 6133352225 |
| 19 | 355687428096000 |
| 20 | 40549021532019 |
| 21 | 4139906028544000 |
| 22 | 464463124401214575 |
| 23 | 51090942171709440000 |
| 24 | 1173011341727225 |
[0,1,1,3,6,35,120,105,1120,19089,362880,133595, 39916800,148397535,458313856,2027025, 1307674368000,6133352225,355687428096000, 40549021532019,4139906028544000, 464463124401214575,51090942171709440000, 1173011341727225] |