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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 6 |
| 5 | 20 |
| 6 | 20 |
| 7 | 105 |
| 8 | 210 |
| 9 | 504 |
| 10 | 504 |
| 11 | 4620 |
| 12 | 4620 |
| 13 | 51480 |
| 14 | 51480 |
| 15 | 9009 |
| 16 | 18018 |
| 17 | 272272 |
| 18 | 272272 |
| 19 | 23279256 |
| 20 | 23279256 |
| 21 | 21162960 |
| 22 | 21162960 |
| 23 | 446185740 |
| 24 | 446185740 |
| 25 | 2059318800 |
| 26 | 2059318800 |
| 27 | 5736673800 |
| 28 | 5736673800 |
| 29 | 22181805360 |
| 30 | 22181805360 |
| 31 | 644658718275 |
| 32 | 1289317436550 |
| 33 | 1213475234400 |
[1,2,3,6,20,20,105,210,504,504,4620,4620,51480, 51480,9009,18018,272272,272272,23279256,23279256, 21162960,21162960,446185740,446185740,2059318800, 2059318800,5736673800,5736673800,22181805360, 22181805360,644658718275,1289317436550, 1213475234400] |