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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 8 |
| 2 | 56 |
| 3 | 392 |
| 4 | 2648 |
| 5 | 17864 |
| 6 | 118760 |
| 7 | 789032 |
| 8 | 5201048 |
| 9 | 34268104 |
| 10 | 224679864 |
| 11 | 1472595144 |
| 12 | 9619740648 |
| 13 | 62823141192 |
| 14 | 409297617672 |
| 15 | 2665987056200 |
| 16 | 17333875251192 |
| 17 | 112680746646856 |
| 18 | 731466943653464 |
| 19 | 4747546469665832 |
| 20 | 30779106675700312 |
| 21 | 199518218638233896 |
| 22 | 1292141318087690824 |
| 23 | 8367300424426139624 |
| 24 | 54141252229349325768 |
| 25 | 350288350314921653160 |
[1,8,56,392,2648,17864,118760,789032,5201048, 34268104,224679864,1472595144,9619740648, 62823141192,409297617672,2665987056200, 17333875251192,112680746646856,731466943653464, 4747546469665832,30779106675700312, 199518218638233896,1292141318087690824, 8367300424426139624,54141252229349325768, 350288350314921653160] |