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Reminder: The OEIS is hiring a new managing editor, and the application deadline is January 26.
Reminder: The OEIS is hiring a new managing editor, and the application deadline is January 26.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 12 |
| 5 | 40 |
| 6 | 160 |
| 7 | 792 |
| 8 | 9408 |
| 9 | 783360 |
| 10 | 55987200 |
| 11 | 35610624000 |
| 12 | 269007298560000 |
[1,1,2,4,12,40,160,792,9408,783360,55987200, 35610624000,269007298560000] |