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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 4 |
| 5 | 6 |
| 6 | 20 |
| 7 | 60 |
| 8 | 120 |
| 9 | 144 |
| 10 | 7920 |
| 11 | 18480 |
| 12 | 18480 |
| 13 | 7920 |
| 14 | 27720 |
| 15 | 2520 |
| 16 | 637560 |
| 17 | 8288280 |
| 18 | 480720240 |
| 19 | 240360120 |
| 20 | 480720240 |
| 21 | 480720240 |
| 22 | 480720240 |
| 23 | 240360120 |
| 24 | 9854764920 |
| 25 | 19709529840 |
| 26 | 9854764920 |
| 27 | 16424608200 |
| 28 | 670124014560 |
| 29 | 88791431929200 |
| 30 | 88791431929200 |
[1,1,2,4,6,20,60,120,144,7920,18480,18480,7920, 27720,2520,637560,8288280,480720240,240360120, 480720240,480720240,480720240,240360120, 9854764920,19709529840,9854764920,16424608200, 670124014560,88791431929200,88791431929200] |