n | a(n) |
---|---|
0 | 1 |
1 | 1 |
2 | 4 |
3 | 27 |
4 | 80 |
5 | 400 |
6 | 1908 |
7 | 6223 |
8 | 31296 |
9 | 116478 |
10 | 450100 |
11 | 1828915 |
12 | 7360848 |
13 | 26906828 |
14 | 95776772 |
15 | 403908975 |
16 | 1421758720 |
17 | 5072014447 |
18 | 18481180644 |
19 | 68350964211 |
20 | 246180936400 |
21 | 827642046294 |
22 | 2958748580084 |
23 | 10294629775620 |
24 | 36607347335232 |
25 | 120800714172500 |
26 | 407951731319860 |
27 | 1405943613730899 |
[1,1,4,27,80,400,1908,6223,31296,116478,450100, 1828915,7360848,26906828,95776772,403908975, 1421758720,5072014447,18481180644,68350964211, 246180936400,827642046294,2958748580084, 10294629775620,36607347335232,120800714172500, 407951731319860,1405943613730899] |