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Reminder: The OEIS is hiring a new managing editor, and the application deadline is January 26.
| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 21 |
| 5 | 75 |
| 6 | 261 |
| 7 | 877 |
| 8 | 2852 |
| 9 | 9020 |
| 10 | 27877 |
| 11 | 84533 |
| 12 | 252331 |
| 13 | 743389 |
| 14 | 2166062 |
| 15 | 6252642 |
| 16 | 17905365 |
| 17 | 50922495 |
| 18 | 143958513 |
| 19 | 404848717 |
| 20 | 1133309336 |
| 21 | 3159610856 |
| 22 | 8776920517 |
| 23 | 24301859561 |
| 24 | 67091484631 |
| 25 | 184734559165 |
| 26 | 507443649506 |
[1,2,6,21,75,261,877,2852,9020,27877,84533,252331, 743389,2166062,6252642,17905365,50922495, 143958513,404848717,1133309336,3159610856, 8776920517,24301859561,67091484631,184734559165, 507443649506] |