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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 120 |
| 2 | 7308 |
| 3 | 303660 |
| 4 | 11098780 |
| 5 | 389449060 |
| 6 | 13642629000 |
| 7 | 486591585480 |
| 8 | 17856935296200 |
| 9 | 678103775949600 |
| 10 | 26726282654771700 |
| 11 | 1094862336960892500 |
| 12 | 46641683693715610500 |
| 13 | 2066075391660447667500 |
| 14 | 95122549872697437090000 |
[1,120,7308,303660,11098780,389449060,13642629000, 486591585480,17856935296200,678103775949600, 26726282654771700,1094862336960892500, 46641683693715610500,2066075391660447667500, 95122549872697437090000] |