n | a(n) |
---|---|
0 | 1 |
1 | 1 |
2 | 4 |
3 | 18 |
4 | 94 |
5 | 529 |
6 | 3135 |
7 | 19270 |
8 | 121732 |
9 | 785496 |
10 | 5155167 |
11 | 34304706 |
12 | 230923653 |
13 | 1569684910 |
14 | 10759159000 |
15 | 74281473504 |
16 | 516089542684 |
17 | 3605685460750 |
18 | 25316226436086 |
19 | 178538289189108 |
20 | 1264131169628799 |
21 | 8982889404251721 |
22 | 64041351551534215 |
[1,1,4,18,94,529,3135,19270,121732,785496,5155167, 34304706,230923653,1569684910,10759159000, 74281473504,516089542684,3605685460750, 25316226436086,178538289189108,1264131169628799, 8982889404251721,64041351551534215] |