n | a(n) |
---|---|
0 | 1 |
1 | 0 |
2 | 2 |
3 | 2 |
4 | 4 |
5 | 8 |
6 | 18 |
7 | 42 |
8 | 102 |
9 | 254 |
10 | 646 |
11 | 1670 |
12 | 4376 |
13 | 11596 |
14 | 31022 |
15 | 83670 |
16 | 227268 |
17 | 621144 |
18 | 1706934 |
19 | 4713558 |
20 | 13072764 |
21 | 36398568 |
22 | 101704038 |
23 | 285095118 |
24 | 801526446 |
25 | 2259520830 |
26 | 6385455594 |
27 | 18086805002 |
28 | 51339636952 |
29 | 146015545604 |
[1,0,2,2,4,8,18,42,102,254,646,1670,4376,11596, 31022,83670,227268,621144,1706934,4713558, 13072764,36398568,101704038,285095118,801526446, 2259520830,6385455594,18086805002,51339636952, 146015545604] |