n | a(n) |
---|---|
0 | 1 |
1 | 1 |
2 | 2 |
3 | 6 |
4 | 20 |
5 | 66 |
6 | 214 |
7 | 688 |
8 | 2206 |
9 | 7070 |
10 | 22660 |
11 | 72634 |
12 | 232830 |
13 | 746352 |
14 | 2392486 |
15 | 7669286 |
16 | 24584436 |
17 | 78807122 |
18 | 252621702 |
19 | 809796400 |
20 | 2595858574 |
[1,1,2,6,20,66,214,688,2206,7070,22660,72634, 232830,746352,2392486,7669286,24584436,78807122, 252621702,809796400,2595858574] |