n | a(n) |
---|---|
0 | 1 |
1 | 4 |
2 | 12 |
3 | 36 |
4 | 116 |
5 | 344 |
6 | 1104 |
7 | 3280 |
8 | 10456 |
9 | 31152 |
10 | 98804 |
11 | 295988 |
12 | 935876 |
13 | 2811540 |
14 | 8870324 |
15 | 26695724 |
16 | 84060148 |
17 | 253376840 |
18 | 796635360 |
19 | 2404558304 |
20 | 7549431884 |
21 | 22820942416 |
22 | 71541295984 |
23 | 216562743948 |
24 | 677938097756 |
25 | 2054922521644 |
[1,4,12,36,116,344,1104,3280,10456,31152,98804, 295988,935876,2811540,8870324,26695724,84060148, 253376840,796635360,2404558304,7549431884, 22820942416,71541295984,216562743948,677938097756, 2054922521644] |