login
The OEIS is supported by
the many generous donors to the OEIS Foundation
.
Hints
(Greetings from
The On-Line Encyclopedia of Integer Sequences
!)
A018681
as a simple table
n
a(n)
1
1
2
2
3
4
4
8
5
16
6
53
7
106
8
212
9
424
10
848
[1,2,4,8,16,53,106,212,424,848]