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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 8 |
| 3 | 11 |
| 4 | 36 |
| 5 | 87 |
| 6 | 256 |
| 7 | 684 |
| 8 | 1932 |
| 9 | 5308 |
| 10 | 14809 |
| 11 | 41025 |
| 12 | 114088 |
| 13 | 316733 |
| 14 | 880136 |
| 15 | 2444724 |
| 16 | 6792145 |
| 17 | 18868672 |
| 18 | 52420409 |
| 19 | 145629432 |
| 20 | 404580097 |
| 21 | 1123976982 |
| 22 | 3122570154 |
| 23 | 8674939898 |
| 24 | 24100237936 |
| 25 | 66953936965 |
| 26 | 186007780911 |
| 27 | 516756709968 |
[1,8,11,36,87,256,684,1932,5308,14809,41025, 114088,316733,880136,2444724,6792145,18868672, 52420409,145629432,404580097,1123976982, 3122570154,8674939898,24100237936,66953936965, 186007780911,516756709968] |