n | a(n) |
---|---|
1 | 1 |
2 | 2 |
3 | 6 |
4 | 18 |
5 | 55 |
6 | 174 |
7 | 566 |
8 | 1868 |
9 | 6237 |
10 | 21050 |
11 | 71666 |
12 | 245696 |
13 | 847317 |
14 | 2937116 |
15 | 10226574 |
16 | 35746292 |
17 | 125380257 |
18 | 441125966 |
19 | 1556301578 |
20 | 18155586993 |
[1,2,6,18,55,174,566,1868,6237,21050,71666,245696, 847317,2937116,10226574,35746292,125380257, 441125966,1556301578,18155586993] |