The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 6 |
| 5 | 10 |
| 6 | 31 |
| 7 | 72 |
| 8 | 143 |
| 9 | 448 |
| 10 | 1113 |
| 11 | 2420 |
| 12 | 7607 |
| 13 | 19644 |
| 14 | 45166 |
| 15 | 142062 |
| 16 | 376222 |
| 17 | 898670 |
| 18 | 2825125 |
| 19 | 7615948 |
| 20 | 18705781 |
| 21 | 58744868 |
| 22 | 160472382 |
| 23 | 402623434 |
| 24 | 1262880382 |
| 25 | 3485281642 |
| 26 | 8893103765 |
| 27 | 27858544576 |
| 28 | 77513822785 |
| 29 | 200511910392 |
| 30 | 627320598639 |
| 31 | 1757135458908 |
| 32 | 4597279553057 |
| 33 | 14365193348236 |
[1,1,1,3,6,10,31,72,143,448,1113,2420,7607,19644, 45166,142062,376222,898670,2825125,7615948, 18705781,58744868,160472382,402623434,1262880382, 3485281642,8893103765,27858544576,77513822785, 200511910392,627320598639,1757135458908, 4597279553057,14365193348236] |