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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 3 |
| 5 | 12 |
| 6 | 30 |
| 7 | 60 |
| 8 | 210 |
| 9 | 840 |
| 10 | 1260 |
| 11 | 2520 |
| 12 | 13860 |
| 13 | 27720 |
| 14 | 180180 |
| 15 | 360360 |
| 16 | 180180 |
| 17 | 720720 |
| 18 | 6126120 |
| 19 | 12252240 |
| 20 | 116396280 |
| 21 | 232792560 |
| 22 | 116396280 |
| 23 | 232792560 |
| 24 | 2677114440 |
| 25 | 5354228880 |
| 26 | 13385572200 |
| 27 | 26771144400 |
| 28 | 40156716600 |
| 29 | 80313433200 |
| 30 | 1164544781400 |
[1,1,2,3,12,30,60,210,840,1260,2520,13860,27720, 180180,360360,180180,720720,6126120,12252240, 116396280,232792560,116396280,232792560, 2677114440,5354228880,13385572200,26771144400, 40156716600,80313433200,1164544781400] |