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| n | a(n) |
|---|---|
| 1 | 144 |
| 2 | 720 |
| 3 | 3600 |
| 4 | 12000 |
| 5 | 40000 |
| 6 | 105000 |
| 7 | 275625 |
| 8 | 617400 |
| 9 | 1382976 |
| 10 | 2765952 |
| 11 | 5531904 |
| 12 | 10160640 |
| 13 | 18662400 |
| 14 | 32076000 |
| 15 | 55130625 |
| 16 | 89842500 |
| 17 | 146410000 |
| 18 | 228399600 |
| 19 | 356303376 |
| 20 | 535927392 |
| 21 | 806105664 |
| 22 | 1175570760 |
| 23 | 1714374025 |
| 24 | 2434614000 |
[144,720,3600,12000,40000,105000,275625,617400, 1382976,2765952,5531904,10160640,18662400, 32076000,55130625,89842500,146410000,228399600, 356303376,535927392,806105664,1175570760, 1714374025,2434614000] |