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| n | a(n) |
|---|---|
| 7 | 120 |
| 8 | 1485 |
| 9 | 9900 |
| 10 | 47190 |
| 11 | 180180 |
| 12 | 585585 |
| 13 | 1681680 |
| 14 | 4375800 |
| 15 | 10501920 |
| 16 | 23556390 |
| 17 | 49884120 |
| 18 | 100524060 |
| 19 | 193993800 |
| 20 | 360380790 |
| 21 | 647214480 |
| 22 | 1127722200 |
| 23 | 1912224600 |
| 24 | 3163606875 |
| 25 | 5118012900 |
| 26 | 8112154050 |
| 27 | 12618906300 |
| 28 | 19293191775 |
| 29 | 29030508000 |
| 30 | 43040883600 |
| 31 | 62941507200 |
[120,1485,9900,47190,180180,585585,1681680, 4375800,10501920,23556390,49884120,100524060, 193993800,360380790,647214480,1127722200, 1912224600,3163606875,5118012900,8112154050, 12618906300,19293191775,29030508000,43040883600, 62941507200] |