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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 11 |
| 3 | 49 |
| 4 | 217 |
| 5 | 858 |
| 6 | 3314 |
| 7 | 11995 |
| 8 | 41921 |
| 9 | 141163 |
| 10 | 462674 |
| 11 | 1480017 |
| 12 | 4644331 |
| 13 | 14332801 |
| 14 | 43628996 |
| 15 | 131248423 |
| 16 | 390921934 |
| 17 | 1154427742 |
| 18 | 3384244322 |
| 19 | 9858374939 |
| 20 | 28560865688 |
| 21 | 82351168539 |
| 22 | 236465407302 |
| 23 | 676536049902 |
| 24 | 1929455222816 |
[1,2,11,49,217,858,3314,11995,41921,141163,462674, 1480017,4644331,14332801,43628996,131248423, 390921934,1154427742,3384244322,9858374939, 28560865688,82351168539,236465407302,676536049902, 1929455222816] |