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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 2 |
| 3 | 3 |
| 4 | 2 |
| 5 | 30 |
| 6 | 18 |
| 7 | 126 |
| 8 | 2 |
| 9 | 504 |
| 10 | 430 |
| 11 | 979 |
| 12 | 18 |
| 13 | 443 |
| 14 | 2198 |
| 15 | 6820 |
| 16 | 976 |
| 17 | 78812 |
| 18 | 7812 |
| 19 | 158080 |
| 20 | 142580 |
| 21 | 248493 |
| 22 | 122870 |
| 23 | 1630792 |
| 24 | 18 |
| 25 | 2777040 |
| 26 | 4511 |
| 27 | 81688176 |
| 28 | 868 |
| 29 | 463347935 |
| 30 | 5921860 |
| 31 | 1211061438 |
| 32 | 26636800 |
| 33 | 598772163 |
| 34 | 40012662 |
| 35 | 145710075 |
| 36 | 135322524 |
| 37 | 40583131393 |
| 38 | 535150200 |
| 39 | 132932362849 |
| 40 | 3936823600 |
[2,2,3,2,30,18,126,2,504,430,979,18,443,2198,6820, 976,78812,7812,158080,142580,248493,122870, 1630792,18,2777040,4511,81688176,868,463347935, 5921860,1211061438,26636800,598772163,40012662, 145710075,135322524,40583131393,535150200, 132932362849,3936823600] |