n | a(n) |
---|---|
0 | 1 |
1 | 1 |
2 | 4 |
3 | 12 |
4 | 45 |
5 | 174 |
6 | 709 |
7 | 2978 |
8 | 12825 |
9 | 56303 |
10 | 251060 |
11 | 1133943 |
12 | 5176926 |
13 | 23851690 |
14 | 110759081 |
15 | 517853840 |
16 | 2435786531 |
17 | 11517940357 |
18 | 54722081630 |
19 | 261089977806 |
20 | 1250479470053 |
21 | 6009884614944 |
22 | 28975052979797 |
23 | 140098515402139 |
24 | 679189779433800 |
25 | 3300702453217325 |
26 | 16076773046682690 |
[1,1,4,12,45,174,709,2978,12825,56303,251060, 1133943,5176926,23851690,110759081,517853840, 2435786531,11517940357,54722081630,261089977806, 1250479470053,6009884614944,28975052979797, 140098515402139,679189779433800,3300702453217325, 16076773046682690] |