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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 | 20269 |
| 10 | 101873 |
| 11 | 520839 |
| 12 | 2690517 |
| 13 | 13976694 |
| 14 | 72797864 |
| 15 | 379609217 |
| 16 | 1981204605 |
| 17 | 10341627330 |
| 18 | 53967714273 |
| 19 | 281504203138 |
| 20 | 1467686630577 |
| 21 | 7649011738137 |
| 22 | 39850489168540 |
| 23 | 207560600018243 |
| 24 | 1080833575339527 |
| 25 | 5627230565442222 |
[1,1,2,5,15,52,203,877,4140,20269,101873,520839, 2690517,13976694,72797864,379609217,1981204605, 10341627330,53967714273,281504203138, 1467686630577,7649011738137,39850489168540, 207560600018243,1080833575339527,5627230565442222] |