The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 21 |
| 5 | 75 |
| 6 | 253 |
| 7 | 774 |
| 8 | 2130 |
| 9 | 5314 |
| 10 | 12169 |
| 11 | 25895 |
| 12 | 51756 |
| 13 | 98034 |
| 14 | 177282 |
| 15 | 307933 |
| 16 | 516327 |
| 17 | 839223 |
| 18 | 1326868 |
| 19 | 2046700 |
| 20 | 3087767 |
| 21 | 4565949 |
| 22 | 6630075 |
| 23 | 9469032 |
| 24 | 13319968 |
| 25 | 18477696 |
| 26 | 25305411 |
| 27 | 34246837 |
| 28 | 45839926 |
| 29 | 60732236 |
| 30 | 79698120 |
| 31 | 103657863 |
| 32 | 133698909 |
| 33 | 171099325 |
| 34 | 217353654 |
| 35 | 274201314 |
| 36 | 343657705 |
[1,1,2,6,21,75,253,774,2130,5314,12169,25895, 51756,98034,177282,307933,516327,839223,1326868, 2046700,3087767,4565949,6630075,9469032,13319968, 18477696,25305411,34246837,45839926,60732236, 79698120,103657863,133698909,171099325,217353654, 274201314,343657705] |