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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 6 |
| 5 | 30 |
| 6 | 10 |
| 7 | 70 |
| 8 | 70 |
| 9 | 210 |
| 10 | 210 |
| 11 | 2310 |
| 12 | 2310 |
| 13 | 30030 |
| 14 | 30030 |
| 15 | 30030 |
| 16 | 30030 |
| 17 | 510510 |
| 18 | 510510 |
| 19 | 9699690 |
| 20 | 1939938 |
| 21 | 646646 |
| 22 | 646646 |
| 23 | 14872858 |
| 24 | 44618574 |
| 25 | 223092870 |
| 26 | 223092870 |
| 27 | 223092870 |
| 28 | 223092870 |
| 29 | 6469693230 |
| 30 | 6469693230 |
| 31 | 200560490130 |
| 32 | 200560490130 |
| 33 | 18232771830 |
[1,2,6,6,30,10,70,70,210,210,2310,2310,30030, 30030,30030,30030,510510,510510,9699690,1939938, 646646,646646,14872858,44618574,223092870, 223092870,223092870,223092870,6469693230, 6469693230,200560490130,200560490130,18232771830] |