n | a(n) |
---|---|
0 | 1 |
1 | 1 |
2 | 3 |
3 | 7 |
4 | 20 |
5 | 66 |
6 | 244 |
7 | 980 |
8 | 4182 |
9 | 18674 |
10 | 86353 |
11 | 410541 |
12 | 1996214 |
13 | 9888844 |
14 | 49760925 |
15 | 253767097 |
16 | 1309154825 |
17 | 6822023553 |
18 | 35865392690 |
19 | 190038440422 |
20 | 1014015337209 |
21 | 5444707218851 |
22 | 29401289997403 |
23 | 159584901816255 |
24 | 870267544114291 |
25 | 4766246752344215 |
26 | 26206635040151511 |
[1,1,3,7,20,66,244,980,4182,18674,86353,410541, 1996214,9888844,49760925,253767097,1309154825, 6822023553,35865392690,190038440422,1014015337209, 5444707218851,29401289997403,159584901816255, 870267544114291,4766246752344215, 26206635040151511] |