n | a(n) |
---|---|
0 | 1 |
1 | 1 |
2 | 1 |
3 | 3 |
4 | 6 |
5 | 16 |
6 | 46 |
7 | 145 |
8 | 480 |
9 | 1820 |
10 | 6809 |
11 | 29214 |
12 | 133441 |
13 | 626090 |
14 | 3053048 |
15 | 16339753 |
16 | 89188931 |
17 | 509642042 |
18 | 3017799873 |
19 | 18798910220 |
20 | 120223747234 |
21 | 802412450368 |
22 | 5475810949896 |
23 | 39019578827168 |
24 | 285084247621276 |
25 | 2151914766238809 |
26 | 16598498118133839 |
27 | 132851511943710915 |
[1,1,1,3,6,16,46,145,480,1820,6809,29214,133441, 626090,3053048,16339753,89188931,509642042, 3017799873,18798910220,120223747234,802412450368, 5475810949896,39019578827168,285084247621276, 2151914766238809,16598498118133839, 132851511943710915] |