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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 5 |
| 2 | 18 |
| 3 | 76 |
| 4 | 296 |
| 5 | 1200 |
| 6 | 4768 |
| 7 | 19136 |
| 8 | 76416 |
| 9 | 305920 |
| 10 | 1223168 |
| 11 | 4893696 |
| 12 | 19572736 |
| 13 | 78295040 |
| 14 | 313171968 |
| 15 | 1252704256 |
| 16 | 5010784256 |
| 17 | 20043202560 |
| 18 | 80172679168 |
| 19 | 320690978816 |
| 20 | 1282763390976 |
| 21 | 5131054612480 |
| 22 | 20524216352768 |
| 23 | 82096869605376 |
| 24 | 328387470032896 |
| 25 | 1313549896908800 |
| 26 | 5254199554080768 |
[1,5,18,76,296,1200,4768,19136,76416,305920, 1223168,4893696,19572736,78295040,313171968, 1252704256,5010784256,20043202560,80172679168, 320690978816,1282763390976,5131054612480, 20524216352768,82096869605376,328387470032896, 1313549896908800,5254199554080768] |