n | a(n) |
---|---|
0 | 0 |
1 | 2 |
2 | 18 |
3 | 116 |
4 | 646 |
5 | 3324 |
6 | 16302 |
7 | 77356 |
8 | 358424 |
9 | 1630988 |
10 | 7317424 |
11 | 32458400 |
12 | 142638568 |
13 | 621948448 |
14 | 2693978986 |
15 | 11602817444 |
16 | 49726594628 |
17 | 212195409348 |
18 | 902038055526 |
19 | 3821542566420 |
20 | 16141064174876 |
21 | 67988725603820 |
22 | 285670814425030 |
23 | 1197613640781032 |
24 | 5010423893820844 |
[0,2,18,116,646,3324,16302,77356,358424,1630988, 7317424,32458400,142638568,621948448,2693978986, 11602817444,49726594628,212195409348,902038055526, 3821542566420,16141064174876,67988725603820, 285670814425030,1197613640781032,5010423893820844] |