A338647 - cp's OEIS frontend

A338647 a(n) = Sum_{k=1..n} 2^(k/gcd(n,k) - 1).

n	a(n)
1	1
2	2
3	4
4	7
5	16
6	22
7	64
8	92
9	223
10	342
11	1024
12	1132
13	4096
14	5462
15	13534
16	21937
17	65536
18	70978
19	262144
20	333472
21	890590
22	1398102
23	4194304
24	4528402
25	16236031
26	22369622
27	57522106
28	88435312
29	268435456
30	272976502
31	1073741824
32	1431677702
33	3679303390
34	5726623062
35	16490405374
36	18543422953

[1, 2, 4, 7, 16, 22, 64, 92, 223, 342, 1024, 1132, 4096, 5462, 13534, 21937, 65536, 70978, 262144, 333472, 890590, 1398102, 4194304, 4528402, 16236031, 22369622, 57522106, 88435312, 268435456, 272976502, 1073741824, 1431677702, 3679303390, 5726623062, 16490405374, 18543422953]

cp's OEIS Frontend

A338647 a(n) = Sum_{k=1..n} 2^(k/gcd(n,k) - 1).

Table of values

List of values