login
The OEIS is supported by
the many generous donors to the OEIS Foundation
.
Hints
(Greetings from
The On-Line Encyclopedia of Integer Sequences
!)
A138077
as a simple table
n
a(n)
1
7
2
13
3
21
4
31
5
57
6
73
7
91
8
133
[7,13,21,31,57,73,91,133]