n | a(n) |
---|---|
0 | 1 |
1 | 4 |
2 | 12 |
3 | 36 |
4 | 108 |
5 | 318 |
6 | 936 |
7 | 2760 |
8 | 8136 |
9 | 23976 |
10 | 70662 |
11 | 208260 |
12 | 613788 |
13 | 1808964 |
14 | 5331420 |
15 | 15712878 |
16 | 46309320 |
17 | 136483800 |
18 | 402247944 |
19 | 1185513624 |
20 | 3493970742 |
21 | 10297504260 |
22 | 30349021740 |
23 | 89445276900 |
24 | 263615006412 |
25 | 776931706398 |
[1,4,12,36,108,318,936,2760,8136,23976,70662, 208260,613788,1808964,5331420,15712878,46309320, 136483800,402247944,1185513624,3493970742, 10297504260,30349021740,89445276900,263615006412, 776931706398] |