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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) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 4 |
| 4 | 16 |
| 5 | 90 |
| 6 | 562 |
| 7 | 3960 |
| 8 | 29311 |
| 9 | 225370 |
| 10 | 1766974 |
| 11 | 14030739 |
| 12 | 112269684 |
| 13 | 903020688 |
[1,1,4,16,90,562,3960,29311,225370,1766974, 14030739,112269684,903020688] |