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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 0 |
| 3 | 1 |
| 4 | 10 |
| 5 | 112 |
| 6 | 1760 |
| 7 | 35150 |
| 8 | 848932 |
| 9 | 24243520 |
| 10 | 805036704 |
| 11 | 30649435140 |
| 12 | 1322299270600 |
| 13 | 64008728200384 |
| 14 | 3447361661136640 |
| 15 | 205070807479444088 |
| 16 | 13388424264027157520 |
| 17 | 953966524932871436800 |
| 18 | 73817914562041635228928 |
[1,0,0,1,10,112,1760,35150,848932,24243520, 805036704,30649435140,1322299270600, 64008728200384,3447361661136640, 205070807479444088,13388424264027157520, 953966524932871436800,73817914562041635228928] |