n | a(n) |
---|---|
0 | 0 |
1 | 1 |
2 | 5 |
3 | 20 |
4 | 87 |
5 | 365 |
6 | 1552 |
7 | 6565 |
8 | 27825 |
9 | 117844 |
10 | 499235 |
11 | 2114729 |
12 | 8958240 |
13 | 37947545 |
14 | 160748653 |
15 | 680941780 |
16 | 2884516383 |
17 | 12219006325 |
18 | 51760543280 |
19 | 219261176861 |
20 | 928805254905 |
21 | 3934482189716 |
22 | 16666734024715 |
23 | 70601418270865 |
[0,1,5,20,87,365,1552,6565,27825,117844,499235, 2114729,8958240,37947545,160748653,680941780, 2884516383,12219006325,51760543280,219261176861, 928805254905,3934482189716,16666734024715, 70601418270865] |