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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 32 |
| 7 | 288 |
| 8 | 2448 |
| 9 | 22080 |
| 10 | 216000 |
| 11 | 2298240 |
| 12 | 26530560 |
| 13 | 330946560 |
| 14 | 4441651200 |
| 15 | 63866880000 |
| 16 | 980037273600 |
| 17 | 15990989414400 |
| 18 | 276529539686400 |
| 19 | 5052853757952000 |
| 20 | 97290972979200000 |
| 21 | 1969085601939456000 |
| 22 | 41794695550992384000 |
| 23 | 928395406320205824000 |
[0,0,0,0,0,32,288,2448,22080,216000,2298240, 26530560,330946560,4441651200,63866880000, 980037273600,15990989414400,276529539686400, 5052853757952000,97290972979200000, 1969085601939456000,41794695550992384000, 928395406320205824000] |