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Reminder: The OEIS is hiring a new managing editor, and the application deadline is January 26.
| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 9 |
| 4 | 28 |
| 5 | 84 |
| 6 | 252 |
| 7 | 757 |
| 8 | 2271 |
| 9 | 6813 |
| 10 | 20440 |
| 11 | 61320 |
| 12 | 183960 |
| 13 | 551881 |
| 14 | 1655643 |
| 15 | 4966929 |
| 16 | 14900788 |
| 17 | 44702364 |
| 18 | 134107092 |
| 19 | 402321277 |
| 20 | 1206963831 |
| 21 | 3620891493 |
| 22 | 10862674480 |
| 23 | 32588023440 |
| 24 | 97764070320 |
| 25 | 293292210961 |
| 26 | 879876632883 |
[1,3,9,28,84,252,757,2271,6813,20440,61320,183960, 551881,1655643,4966929,14900788,44702364, 134107092,402321277,1206963831,3620891493, 10862674480,32588023440,97764070320,293292210961, 879876632883] |