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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 10 |
| 3 | 29 |
| 4 | 87 |
| 5 | 280 |
| 6 | 876 |
| 7 | 2735 |
| 8 | 8583 |
| 9 | 26900 |
| 10 | 84274 |
| 11 | 264107 |
| 12 | 827651 |
| 13 | 2593568 |
| 14 | 8127490 |
| 15 | 25469197 |
| 16 | 79812833 |
| 17 | 250109752 |
| 18 | 783769936 |
| 19 | 2456102483 |
| 20 | 7696696911 |
| 21 | 24119166438 |
| 22 | 75582316528 |
| 23 | 236852570799 |
| 24 | 742225734425 |
| 25 | 2325915393694 |
| 26 | 7288729246884 |
[2,10,29,87,280,876,2735,8583,26900,84274,264107, 827651,2593568,8127490,25469197,79812833, 250109752,783769936,2456102483,7696696911, 24119166438,75582316528,236852570799,742225734425, 2325915393694,7288729246884] |