n | a(n) |
---|---|
0 | 1 |
1 | 0 |
2 | 1 |
3 | 1 |
4 | 5 |
5 | 16 |
6 | 65 |
7 | 260 |
8 | 1085 |
9 | 4600 |
10 | 19845 |
11 | 86725 |
12 | 383251 |
13 | 1709566 |
14 | 7687615 |
15 | 34812519 |
16 | 158614405 |
17 | 726612216 |
18 | 3344696501 |
19 | 15462729645 |
20 | 71763732545 |
21 | 334236300200 |
22 | 1561686608685 |
23 | 7318223046860 |
24 | 34386154568375 |
25 | 161970182441556 |
26 | 764676831501575 |
27 | 3617755131480841 |
[1,0,1,1,5,16,65,260,1085,4600,19845,86725,383251, 1709566,7687615,34812519,158614405,726612216, 3344696501,15462729645,71763732545,334236300200, 1561686608685,7318223046860,34386154568375, 161970182441556,764676831501575,3617755131480841] |