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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 | 5 |
| 4 | 15 |
| 5 | 52 |
| 6 | 203 |
| 7 | 877 |
| 8 | 4140 |
| 9 | 21147 |
| 10 | 115974 |
| 11 | 678559 |
| 12 | 4213465 |
| 13 | 27643007 |
| 14 | 190884307 |
| 15 | 1382802389 |
| 16 | 10478516523 |
| 17 | 82847813908 |
| 18 | 681895648039 |
| 19 | 5830788687491 |
| 20 | 51702731250650 |
| 21 | 474630475600569 |
| 22 | 4503991075480297 |
| 23 | 44120379612630694 |
| 24 | 445584481578266277 |
| 25 | 4634070027874688433 |
[1,1,2,5,15,52,203,877,4140,21147,115974,678559, 4213465,27643007,190884307,1382802389,10478516523, 82847813908,681895648039,5830788687491, 51702731250650,474630475600569,4503991075480297, 44120379612630694,445584481578266277, 4634070027874688433] |