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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 4 |
| 5 | 20 |
| 6 | 24 |
| 7 | 168 |
| 8 | 192 |
| 9 | 1728 |
| 10 | 17280 |
| 11 | 190080 |
| 12 | 207360 |
| 13 | 2695680 |
| 14 | 2903040 |
| 15 | 43545600 |
| 16 | 696729600 |
| 17 | 11844403200 |
| 18 | 12541132800 |
| 19 | 238281523200 |
| 20 | 250822656000 |
| 21 | 5267275776000 |
| 22 | 115880067072000 |
| 23 | 2665241542656000 |
| 24 | 2781121609728000 |
| 25 | 69528040243200000 |
| 26 | 1807729046323200000 |
[1,1,2,3,4,20,24,168,192,1728,17280,190080,207360, 2695680,2903040,43545600,696729600,11844403200, 12541132800,238281523200,250822656000, 5267275776000,115880067072000,2665241542656000, 2781121609728000,69528040243200000, 1807729046323200000] |