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| n | a(n) |
|---|---|
| 2 | 1 |
| 3 | 2 |
| 4 | 6 |
| 5 | 12 |
| 6 | 60 |
| 7 | 120 |
| 8 | 1260 |
| 9 | 840 |
| 10 | 0 |
| 11 | 2520 |
| 12 | 27720 |
| 13 | 55440 |
| 14 | 0 |
| 15 | 720720 |
| 16 | 1081080 |
| 17 | 2162160 |
| 18 | 61261200 |
| 19 | 36756720 |
| 20 | 1396755360 |
| 21 | 2327925600 |
| 22 | 0 |
| 23 | 698377680 |
| 24 | 16062686640 |
| 25 | 48188059920 |
| 26 | 0 |
| 27 | 749592043200 |
| 28 | 160626866400 |
| 29 | 240940299600 |
| 30 | 0 |
| 31 | 6987268688400 |
[1,2,6,12,60,120,1260,840,0,2520,27720,55440,0, 720720,1081080,2162160,61261200,36756720, 1396755360,2327925600,0,698377680,16062686640, 48188059920,0,749592043200,160626866400, 240940299600,0,6987268688400] |