n | a(n) |
---|---|
0 | 1 |
1 | 1 |
2 | 3 |
3 | 9 |
4 | 25 |
5 | 69 |
6 | 189 |
7 | 519 |
8 | 1428 |
9 | 3930 |
10 | 10812 |
11 | 29742 |
12 | 81816 |
13 | 225070 |
14 | 619156 |
15 | 1703262 |
16 | 4685565 |
17 | 12889687 |
18 | 35458707 |
19 | 97544655 |
20 | 268339161 |
21 | 738183999 |
22 | 2030697309 |
23 | 5586319365 |
24 | 15367609920 |
25 | 42275319276 |
26 | 116296719448 |
[1,1,3,9,25,69,189,519,1428,3930,10812,29742, 81816,225070,619156,1703262,4685565,12889687, 35458707,97544655,268339161,738183999,2030697309, 5586319365,15367609920,42275319276,116296719448] |