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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 12 |
| 4 | 260 |
| 5 | 5720 |
| 6 | 314248 |
| 7 | 17255072 |
| 8 | 1769058016 |
| 9 | 181357735680 |
| 10 | 29880655637760 |
| 11 | 4923158441956352 |
| 12 | 1189676108826729472 |
| 13 | 287484053261423565824 |
| 14 | 95784714773484796761088 |
| 15 | 31913810779214031287095296 |
| 16 | 2804341960426298188743438336 |
| 17 | 1232120770958699233546743119872 |
[1,3,12,260,5720,314248,17255072,1769058016, 181357735680,29880655637760,4923158441956352, 1189676108826729472,287484053261423565824, 95784714773484796761088, 31913810779214031287095296, 2804341960426298188743438336, 1232120770958699233546743119872] |