n | a(n) |
---|---|
1 | 1 |
2 | 1 |
3 | 0 |
4 | 0 |
5 | 2 |
6 | 2 |
7 | 4 |
8 | 27 |
9 | 78 |
10 | 222 |
11 | 816 |
12 | 2736 |
13 | 8784 |
14 | 29704 |
15 | 100408 |
16 | 334889 |
17 | 1128036 |
18 | 3819368 |
19 | 12912484 |
20 | 43771606 |
21 | 148863396 |
22 | 506943540 |
23 | 1729339848 |
24 | 5911769970 |
25 | 20242876176 |
26 | 69422168880 |
27 | 238465602096 |
28 | 820352668488 |
29 | 2826032713656 |
[1,1,0,0,2,2,4,27,78,222,816,2736,8784,29704, 100408,334889,1128036,3819368,12912484,43771606, 148863396,506943540,1729339848,5911769970, 20242876176,69422168880,238465602096,820352668488, 2826032713656] |