The OEIS is supported by the many generous donors to the OEIS Foundation.
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 | 5 |
| 4 | 13 |
| 5 | 40 |
| 6 | 133 |
| 7 | 485 |
| 8 | 1887 |
| 9 | 7872 |
| 10 | 34648 |
| 11 | 161108 |
| 12 | 784195 |
| 13 | 3999850 |
| 14 | 21209261 |
| 15 | 117164889 |
| 16 | 669800056 |
| 17 | 3968343015 |
| 18 | 24252416366 |
| 19 | 153029073580 |
| 20 | 992860849454 |
| 21 | 6632168652281 |
| 22 | 45444519380882 |
| 23 | 319738889742372 |
| 24 | 2303340195173602 |
| 25 | 17001774682931823 |
| 26 | 128258904114067371 |
[1,1,2,5,13,40,133,485,1887,7872,34648,161108, 784195,3999850,21209261,117164889,669800056, 3968343015,24252416366,153029073580,992860849454, 6632168652281,45444519380882,319738889742372, 2303340195173602,17001774682931823, 128258904114067371] |