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| n | a(n) |
|---|---|
| 8 | 165 |
| 9 | 2200 |
| 10 | 15730 |
| 11 | 80080 |
| 12 | 325325 |
| 13 | 1121120 |
| 14 | 3403400 |
| 15 | 9335040 |
| 16 | 23556390 |
| 17 | 55426800 |
| 18 | 122862740 |
| 19 | 258658400 |
| 20 | 520550030 |
| 21 | 1006778080 |
| 22 | 1879537000 |
| 23 | 3399510400 |
| 24 | 5975701875 |
| 25 | 10236025800 |
| 26 | 17125658550 |
| 27 | 28042014000 |
| 28 | 45017447475 |
| 29 | 70963464000 |
| 30 | 109993369200 |
| 31 | 167844019200 |
[165,2200,15730,80080,325325,1121120,3403400, 9335040,23556390,55426800,122862740,258658400, 520550030,1006778080,1879537000,3399510400, 5975701875,10236025800,17125658550,28042014000, 45017447475,70963464000,109993369200,167844019200] |