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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 4 |
| 4 | 2 |
| 5 | 18 |
| 6 | 6 |
| 7 | 96 |
| 8 | 24 |
| 9 | 600 |
| 10 | 120 |
| 11 | 4320 |
| 12 | 720 |
| 13 | 35280 |
| 14 | 5040 |
| 15 | 322560 |
| 16 | 40320 |
| 17 | 3265920 |
| 18 | 362880 |
| 19 | 36288000 |
| 20 | 3628800 |
| 21 | 439084800 |
| 22 | 39916800 |
| 23 | 5748019200 |
| 24 | 479001600 |
| 25 | 80951270400 |
| 26 | 6227020800 |
| 27 | 1220496076800 |
| 28 | 87178291200 |
| 29 | 19615115520000 |
| 30 | 1307674368000 |
| 31 | 334764638208000 |
[1,1,4,2,18,6,96,24,600,120,4320,720,35280,5040, 322560,40320,3265920,362880,36288000,3628800, 439084800,39916800,5748019200,479001600, 80951270400,6227020800,1220496076800,87178291200, 19615115520000,1307674368000,334764638208000] |