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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 12 |
| 5 | 60 |
| 6 | 60 |
| 7 | 420 |
| 8 | 1680 |
| 9 | 5040 |
| 10 | 5040 |
| 11 | 55440 |
| 12 | 332640 |
| 13 | 4324320 |
| 14 | 8648640 |
| 15 | 43243200 |
| 16 | 172972800 |
| 17 | 2940537600 |
| 18 | 8821612800 |
| 19 | 167610643200 |
| 20 | 335221286400 |
| 21 | 7039647014400 |
| 22 | 14079294028800 |
| 23 | 323823762662400 |
| 24 | 647647525324800 |
| 25 | 3238237626624000 |
| 26 | 6476475253248000 |
[1,1,2,6,12,60,60,420,1680,5040,5040,55440,332640, 4324320,8648640,43243200,172972800,2940537600, 8821612800,167610643200,335221286400, 7039647014400,14079294028800,323823762662400, 647647525324800,3238237626624000,6476475253248000] |