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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 2 |
| 5 | 3 |
| 6 | 120 |
| 7 | 720 |
| 8 | 1008 |
| 9 | 40320 |
| 10 | 362880 |
| 11 | 45360 |
| 12 | 39916800 |
| 13 | 68428800 |
| 14 | 6227020800 |
| 15 | 87178291200 |
| 16 | 1307674368000 |
| 17 | 1046139494400 |
| 18 | 355687428096000 |
| 19 | 376610217984000 |
| 20 | 40548366802944000 |
| 21 | 2432902008176640000 |
| 22 | 5676771352412160000 |
| 23 | 40142883134914560000 |
| 24 | 25852016738884976640000 |
[1,1,1,2,2,3,120,720,1008,40320,362880,45360, 39916800,68428800,6227020800,87178291200, 1307674368000,1046139494400,355687428096000, 376610217984000,40548366802944000, 2432902008176640000,5676771352412160000, 40142883134914560000,25852016738884976640000] |