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Reminder: The OEIS is hiring a new managing editor, and the application deadline is January 26.
| n | a(n) |
|---|---|
| 3 | 0 |
| 4 | 2 |
| 5 | 6 |
| 6 | 18 |
| 7 | 62 |
| 8 | 210 |
| 9 | 728 |
| 10 | 2570 |
| 11 | 9198 |
| 12 | 33288 |
| 13 | 121574 |
| 14 | 447394 |
| 15 | 1657008 |
| 16 | 6170930 |
| 17 | 23091222 |
| 18 | 86767016 |
| 19 | 327235610 |
| 20 | 1238188770 |
| 21 | 4698767640 |
[0,2,6,18,62,210,728,2570,9198,33288,121574, 447394,1657008,6170930,23091222,86767016, 327235610,1238188770,4698767640] |