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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 96 |
| 7 | 1904 |
| 8 | 23040 |
| 9 | 221184 |
| 10 | 1858560 |
| 11 | 14353152 |
| 12 | 104742912 |
| 13 | 734769152 |
| 14 | 5010432000 |
| 15 | 33464217600 |
| 16 | 220066480128 |
| 17 | 1430279159808 |
| 18 | 9212045819904 |
| 19 | 58914039332864 |
| 20 | 374665295953920 |
| 21 | 2371935399837696 |
| 22 | 14960708435312640 |
| 23 | 94072038170296320 |
| 24 | 589975504803594240 |
[0,0,0,0,0,0,96,1904,23040,221184,1858560, 14353152,104742912,734769152,5010432000, 33464217600,220066480128,1430279159808, 9212045819904,58914039332864,374665295953920, 2371935399837696,14960708435312640, 94072038170296320,589975504803594240] |