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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 12 |
| 5 | 60 |
| 6 | 20 |
| 7 | 140 |
| 8 | 280 |
| 9 | 2520 |
| 10 | 2520 |
| 11 | 27720 |
| 12 | 27720 |
| 13 | 360360 |
| 14 | 360360 |
| 15 | 72072 |
| 16 | 144144 |
| 17 | 2450448 |
| 18 | 272272 |
| 19 | 5173168 |
| 20 | 5173168 |
| 21 | 739024 |
| 22 | 739024 |
| 23 | 16997552 |
| 24 | 16997552 |
| 25 | 424938800 |
| 26 | 424938800 |
| 27 | 11473347600 |
| 28 | 11473347600 |
| 29 | 332727080400 |
| 30 | 332727080400 |
[1,2,6,12,60,20,140,280,2520,2520,27720,27720, 360360,360360,72072,144144,2450448,272272,5173168, 5173168,739024,739024,16997552,16997552,424938800, 424938800,11473347600,11473347600,332727080400, 332727080400] |