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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 150 |
| 3 | 8400 |
| 4 | 150300 |
| 5 | 1394400 |
| 6 | 8656200 |
| 7 | 40356000 |
| 8 | 153679800 |
| 9 | 498153600 |
| 10 | 1431378900 |
| 11 | 3705270000 |
| 12 | 8863150800 |
| 13 | 19694152800 |
| 14 | 41402744400 |
| 15 | 82382680800 |
| 16 | 157380332400 |
| 17 | 288000115200 |
| 18 | 511088547150 |
| 19 | 875865085200 |
| 20 | 1465721632200 |
| 21 | 2382961862400 |
| 22 | 3801687211800 |
| 23 | 5918070367200 |
| 24 | 9075809181600 |
[0,150,8400,150300,1394400,8656200,40356000, 153679800,498153600,1431378900,3705270000, 8863150800,19694152800,41402744400,82382680800, 157380332400,288000115200,511088547150, 875865085200,1465721632200,2382961862400, 3801687211800,5918070367200,9075809181600] |