login
The OEIS is supported by
the many generous donors to the OEIS Foundation
.
Hints
(Greetings from
The On-Line Encyclopedia of Integer Sequences
!)
A268571
as a simple table
n
a(n)
1
0
2
0
3
1
4
1
5
2
6
5
7
16
8
52
9
205
10
863
[0,0,1,1,2,5,16,52,205,863]