n | a(n) |
---|---|
1 | 1 |
2 | 0 |
3 | 1 |
4 | 1 |
5 | 3 |
6 | 7 |
7 | 16 |
8 | 45 |
9 | 110 |
10 | 308 |
11 | 819 |
12 | 2275 |
13 | 6328 |
14 | 17748 |
15 | 50388 |
16 | 143412 |
17 | 411939 |
18 | 1187329 |
19 | 3441559 |
20 | 10015005 |
21 | 29255655 |
22 | 85766655 |
23 | 252201690 |
24 | 743819115 |
25 | 2199446652 |
26 | 6519727800 |
27 | 19369551936 |
28 | 57665571072 |
29 | 172011364452 |
30 | 514021640564 |
31 | 1538650042952 |
[1,0,1,1,3,7,16,45,110,308,819,2275,6328,17748, 50388,143412,411939,1187329,3441559,10015005, 29255655,85766655,252201690,743819115,2199446652, 6519727800,19369551936,57665571072,172011364452, 514021640564,1538650042952] |