login
The OEIS is supported by
the many generous donors to the OEIS Foundation
.
Hints
(Greetings from
The On-Line Encyclopedia of Integer Sequences
!)
A245890
as a simple table
n
a(n)
1
1
2
1
3
3
4
9
5
37
6
165
7
834
8
4515
[1,1,3,9,37,165,834,4515]