n | a(n) |
---|---|
0 | 0 |
1 | 1 |
2 | 10 |
3 | 57 |
4 | 260 |
5 | 1055 |
6 | 3990 |
7 | 14413 |
8 | 50440 |
9 | 172539 |
10 | 580250 |
11 | 1926089 |
12 | 6328140 |
13 | 20619703 |
14 | 66732190 |
15 | 214742085 |
16 | 687698960 |
17 | 2193154547 |
18 | 6968850210 |
19 | 22073006401 |
20 | 69714716500 |
21 | 219623377071 |
22 | 690291036710 |
[0,1,10,57,260,1055,3990,14413,50440,172539, 580250,1926089,6328140,20619703,66732190, 214742085,687698960,2193154547,6968850210, 22073006401,69714716500,219623377071,690291036710] |