n | a(n) |
---|---|
0 | 0 |
1 | 1 |
2 | 4 |
3 | 18 |
4 | 83 |
5 | 387 |
6 | 1815 |
7 | 8541 |
8 | 40276 |
9 | 190182 |
10 | 898844 |
11 | 4250780 |
12 | 20111394 |
13 | 95181166 |
14 | 450565602 |
15 | 2133227418 |
16 | 10101126723 |
17 | 47834649675 |
18 | 226540406571 |
19 | 1072931019393 |
20 | 5081776592061 |
21 | 24069823974879 |
22 | 114009427284309 |
[0,1,4,18,83,387,1815,8541,40276,190182,898844, 4250780,20111394,95181166,450565602,2133227418, 10101126723,47834649675,226540406571, 1072931019393,5081776592061,24069823974879, 114009427284309] |