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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 789696 |
| 5 | 10664384 |
| 6 | 48391584 |
| 7 | 132995984 |
| 8 | 276318288 |
| 9 | 482853584 |
| 10 | 752575536 |
| 11 | 1083942480 |
| 12 | 1475455440 |
| 13 | 1926184124 |
| 14 | 2435663832 |
| 15 | 3003713808 |
| 16 | 3630272848 |
| 17 | 4315325376 |
| 18 | 5058867816 |
| 19 | 5860899668 |
| 20 | 6721420864 |
| 21 | 7640431404 |
| 22 | 8617931288 |
[0,0,0,789696,10664384,48391584,132995984, 276318288,482853584,752575536,1083942480, 1475455440,1926184124,2435663832,3003713808, 3630272848,4315325376,5058867816,5860899668, 6721420864,7640431404,8617931288] |