A102359 - cp's OEIS frontend

A102359 a(n) = sigma((4^n - 1)/3), where sigma(n) is the sum of positive divisors of n.

n	a(n)
1	1
2	6
3	32
4	108
5	384
6	2688
7	5632
8	27864
9	153920
10	499968
11	1477440
12	11708928
13	22380544
14	115568640
15	620101632
16	1826150832
17	5726797824
18	54044390400
19	91626668032
20	555102471168
21	2352412508160
22	7458459886080
23	23955459951744
24	199536712962048
25	425355918188544
26	1849167560835072

[1, 6, 32, 108, 384, 2688, 5632, 27864, 153920, 499968, 1477440, 11708928, 22380544, 115568640, 620101632, 1826150832, 5726797824, 54044390400, 91626668032, 555102471168, 2352412508160, 7458459886080, 23955459951744, 199536712962048, 425355918188544, 1849167560835072]

cp's OEIS Frontend

A102359 a(n) = sigma((4^n - 1)/3), where sigma(n) is the sum of positive divisors of n.

Table of values

List of values