n | a(n) |
---|---|
0 | 1 |
1 | 1 |
2 | 1 |
3 | 2 |
4 | 4 |
5 | 10 |
6 | 26 |
7 | 73 |
8 | 213 |
9 | 645 |
10 | 2007 |
11 | 6391 |
12 | 20741 |
13 | 68407 |
14 | 228753 |
15 | 774162 |
16 | 2647548 |
17 | 9138342 |
18 | 31802118 |
19 | 111489492 |
20 | 393442848 |
21 | 1396771812 |
22 | 4985732628 |
23 | 17884908282 |
24 | 64449398994 |
25 | 233220788850 |
26 | 847211744806 |
27 | 3088649627798 |
[1,1,1,2,4,10,26,73,213,645,2007,6391,20741,68407, 228753,774162,2647548,9138342,31802118,111489492, 393442848,1396771812,4985732628,17884908282, 64449398994,233220788850,847211744806, 3088649627798] |