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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 288 |
| 3 | 3072 |
| 4 | 38880 |
| 5 | 110592 |
| 6 | 654720 |
| 7 | 1161216 |
| 8 | 4964832 |
| 9 | 6758400 |
| 10 | 23385024 |
| 11 | 27509760 |
| 12 | 84872832 |
| 13 | 88584192 |
| 14 | 246470400 |
| 15 | 241330176 |
| 16 | 635597280 |
| 17 | 579280896 |
| 18 | 1432192416 |
| 19 | 1261992960 |
| 20 | 3030460992 |
| 21 | 2543861760 |
| 22 | 5832383616 |
| 23 | 4806715392 |
| 24 | 10864625280 |
| 25 | 8616886272 |
| 26 | 18780246720 |
[1,0,288,3072,38880,110592,654720,1161216,4964832, 6758400,23385024,27509760,84872832,88584192, 246470400,241330176,635597280,579280896, 1432192416,1261992960,3030460992,2543861760, 5832383616,4806715392,10864625280,8616886272, 18780246720] |