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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 8 |
| 4 | 10 |
| 5 | 110 |
| 6 | 406 |
| 7 | 504 |
| 8 | 1892 |
| 9 | 7150 |
| 10 | 27170 |
| 11 | 311168 |
| 12 | 1192516 |
| 13 | 1528436 |
| 14 | 17681020 |
| 15 | 68346800 |
| 16 | 88256520 |
| 17 | 342551190 |
| 18 | 1331805570 |
| 19 | 5185791600 |
| 20 | 20220038300 |
| 21 | 78937755820 |
| 22 | 308513659740 |
| 23 | 1207002506320 |
| 24 | 4726599121400 |
| 25 | 18525219137100 |
[1,3,8,10,110,406,504,1892,7150,27170,311168, 1192516,1528436,17681020,68346800,88256520, 342551190,1331805570,5185791600,20220038300, 78937755820,308513659740,1207002506320, 4726599121400,18525219137100] |