| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 10 |
| 3 | 31 |
| 4 | 97 |
| 5 | 302 |
| 6 | 941 |
| 7 | 2931 |
| 8 | 9130 |
| 9 | 28439 |
| 10 | 88585 |
| 11 | 275934 |
| 12 | 859509 |
| 13 | 2677291 |
| 14 | 8339514 |
| 15 | 25976815 |
| 16 | 80915377 |
| 17 | 252043918 |
| 18 | 785093501 |
| 19 | 2445493667 |
| 20 | 7617486666 |
| 21 | 23727766663 |
| 22 | 73909799321 |
| 23 | 230222191294 |
| 24 | 717120839877 |
| 25 | 2233765112283 |
[1,3,10,31,97,302,941,2931,9130,28439,88585, 275934,859509,2677291,8339514,25976815,80915377, 252043918,785093501,2445493667,7617486666, 23727766663,73909799321,230222191294,717120839877, 2233765112283] |