n | a(n) |
---|---|
1 | 0 |
2 | 0 |
3 | 6 |
4 | 24 |
5 | 92 |
6 | 318 |
7 | 1056 |
8 | 3406 |
9 | 10770 |
10 | 33542 |
11 | 103226 |
12 | 314634 |
13 | 951396 |
14 | 2857604 |
15 | 8534022 |
16 | 25360354 |
17 | 75037878 |
18 | 221184144 |
19 | 649773710 |
20 | 1903099818 |
21 | 5558851080 |
22 | 16197428578 |
23 | 47091498180 |
24 | 136634149236 |
25 | 395704051072 |
26 | 1144040493756 |
[0,0,6,24,92,318,1056,3406,10770,33542,103226, 314634,951396,2857604,8534022,25360354,75037878, 221184144,649773710,1903099818,5558851080, 16197428578,47091498180,136634149236,395704051072, 1144040493756] |