n | a(n) |
---|---|
1 | 1 |
2 | 4 |
3 | 18 |
4 | 84 |
5 | 394 |
6 | 1836 |
7 | 8468 |
8 | 38632 |
9 | 174426 |
10 | 780156 |
11 | 3460156 |
12 | 15232344 |
13 | 66613828 |
14 | 289609144 |
15 | 1252537704 |
16 | 5391904208 |
17 | 23114020090 |
18 | 98712408732 |
19 | 420134237996 |
20 | 1782630641656 |
21 | 7542431851692 |
22 | 31830492787880 |
23 | 134013965210008 |
24 | 563006802201264 |
25 | 2360517093477284 |
[1,4,18,84,394,1836,8468,38632,174426,780156, 3460156,15232344,66613828,289609144,1252537704, 5391904208,23114020090,98712408732,420134237996, 1782630641656,7542431851692,31830492787880, 134013965210008,563006802201264,2360517093477284] |