n | a(n) |
---|---|
0 | 1 |
1 | 1 |
2 | 4 |
3 | 9 |
4 | 30 |
5 | 94 |
6 | 328 |
7 | 1165 |
8 | 4294 |
9 | 16134 |
10 | 61752 |
11 | 239610 |
12 | 940716 |
13 | 3729324 |
14 | 14908176 |
15 | 60026109 |
16 | 243211206 |
17 | 990897478 |
18 | 4057013080 |
19 | 16683617326 |
20 | 68879236036 |
21 | 285388549188 |
22 | 1186296731376 |
23 | 4945790840338 |
24 | 20675513743900 |
25 | 86648395759516 |
[1,1,4,9,30,94,328,1165,4294,16134,61752,239610, 940716,3729324,14908176,60026109,243211206, 990897478,4057013080,16683617326,68879236036, 285388549188,1186296731376,4945790840338, 20675513743900,86648395759516] |