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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 8 |
| 2 | 42 |
| 3 | 204 |
| 4 | 972 |
| 5 | 4608 |
| 6 | 21816 |
| 7 | 103248 |
| 8 | 488592 |
| 9 | 2312064 |
| 10 | 10940832 |
| 11 | 51772608 |
| 12 | 244990656 |
| 13 | 1159308288 |
| 14 | 5485905792 |
| 15 | 25959585024 |
| 16 | 122842075392 |
| 17 | 581294942208 |
| 18 | 2750717200896 |
| 19 | 13016533552128 |
| 20 | 61594898107392 |
| 21 | 291470187331584 |
| 22 | 1379251735345152 |
| 23 | 6526689288081408 |
| 24 | 30884625316417536 |
[1,8,42,204,972,4608,21816,103248,488592,2312064, 10940832,51772608,244990656,1159308288,5485905792, 25959585024,122842075392,581294942208, 2750717200896,13016533552128,61594898107392, 291470187331584,1379251735345152,6526689288081408, 30884625316417536] |