n | a(n) |
---|---|
0 | 0 |
1 | 0 |
2 | 2 |
3 | 12 |
4 | 42 |
5 | 115 |
6 | 288 |
7 | 738 |
8 | 2020 |
9 | 5751 |
10 | 16362 |
11 | 45697 |
12 | 125538 |
13 | 342318 |
14 | 933050 |
15 | 2547630 |
16 | 6960042 |
17 | 18990309 |
18 | 51699042 |
19 | 140439411 |
20 | 380871538 |
21 | 1031705466 |
22 | 2792009100 |
23 | 7548723827 |
24 | 20389716864 |
25 | 55020917232 |
26 | 148334534420 |
27 | 399562167420 |
28 | 1075432476492 |
[0,0,2,12,42,115,288,738,2020,5751,16362,45697, 125538,342318,933050,2547630,6960042,18990309, 51699042,140439411,380871538,1031705466, 2792009100,7548723827,20389716864,55020917232, 148334534420,399562167420,1075432476492] |