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| n | a(n) |
|---|---|
| 0 | 3 |
| 1 | 10 |
| 2 | 27 |
| 3 | 71 |
| 4 | 186 |
| 5 | 487 |
| 6 | 1275 |
| 7 | 3338 |
| 8 | 8739 |
| 9 | 22879 |
| 10 | 59898 |
| 11 | 156815 |
| 12 | 410547 |
| 13 | 1074826 |
| 14 | 2813931 |
| 15 | 7366967 |
| 16 | 19286970 |
| 17 | 50493943 |
| 18 | 132194859 |
| 19 | 346090634 |
| 20 | 906077043 |
| 21 | 2372140495 |
| 22 | 6210344442 |
| 23 | 16258892831 |
| 24 | 42566334051 |
| 25 | 111440109322 |
| 26 | 291753993915 |
| 27 | 763821872423 |
| 28 | 1999711623354 |
[3,10,27,71,186,487,1275,3338,8739,22879,59898, 156815,410547,1074826,2813931,7366967,19286970, 50493943,132194859,346090634,906077043,2372140495, 6210344442,16258892831,42566334051,111440109322, 291753993915,763821872423,1999711623354] |