n | a(n) |
---|---|
0 | 1 |
1 | 0 |
2 | 1 |
3 | 1 |
4 | 2 |
5 | 5 |
6 | 15 |
7 | 50 |
8 | 181 |
9 | 697 |
10 | 2821 |
11 | 11892 |
12 | 51874 |
13 | 232974 |
14 | 1073070 |
15 | 5053029 |
16 | 24264565 |
17 | 118570292 |
18 | 588567257 |
19 | 2963358162 |
20 | 15114174106 |
21 | 78004013763 |
22 | 406971280545 |
23 | 2144659072330 |
24 | 11407141925639 |
25 | 61197287846831 |
[1,0,1,1,2,5,15,50,181,697,2821,11892,51874, 232974,1073070,5053029,24264565,118570292, 588567257,2963358162,15114174106,78004013763, 406971280545,2144659072330,11407141925639, 61197287846831] |