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Reminder: The OEIS is hiring a new managing editor, and the application deadline is January 26.
| n | a(n) |
|---|---|
| 2 | 1 |
| 3 | 6 |
| 4 | 18 |
| 5 | 50 |
| 6 | 156 |
| 7 | 508 |
| 8 | 1724 |
| 9 | 6018 |
| 10 | 21440 |
| 11 | 77632 |
| 12 | 284706 |
| 13 | 1055162 |
| 14 | 3944956 |
| 15 | 14858934 |
| 16 | 56325420 |
| 17 | 214698578 |
| 18 | 822373244 |
| 19 | 3163606784 |
| 20 | 12217121138 |
| 21 | 47343356398 |
| 22 | 184038696776 |
| 23 | 717456797490 |
| 24 | 2804219712064 |
| 25 | 10986639618642 |
[1,6,18,50,156,508,1724,6018,21440,77632,284706, 1055162,3944956,14858934,56325420,214698578, 822373244,3163606784,12217121138,47343356398, 184038696776,717456797490,2804219712064, 10986639618642] |