n | a(n) |
---|---|
0 | 1 |
1 | 1 |
2 | 2 |
3 | 5 |
4 | 15 |
5 | 52 |
6 | 203 |
7 | 877 |
8 | 4140 |
9 | 17007 |
10 | 64077 |
11 | 231180 |
12 | 821132 |
13 | 2918753 |
14 | 10483154 |
15 | 38264066 |
16 | 142423894 |
17 | 533308705 |
18 | 1995314365 |
19 | 7437442700 |
20 | 27604521795 |
21 | 102095937121 |
22 | 376790770192 |
23 | 1389739254904 |
24 | 5130664114644 |
25 | 18964932885093 |
26 | 70170215134155 |
27 | 259770146382666 |
[1,1,2,5,15,52,203,877,4140,17007,64077,231180, 821132,2918753,10483154,38264066,142423894, 533308705,1995314365,7437442700,27604521795, 102095937121,376790770192,1389739254904, 5130664114644,18964932885093,70170215134155, 259770146382666] |