A102360 - cp's OEIS frontend

A102360 a(n) = sigma((7^n - 1)/6), where sigma(n) is the sum of positive divisors of n.

n	a(n)
1	1
2	15
3	80
4	961
5	2802
6	52800
7	142020
8	2347506
9	10512320
10	96837120
11	329849040
12	8619170560
13	16148168402
14	221483030400
15	1146781040640
16	14442767744328
17	38774519976900
18	813898294809600
19	1904350030969680
20	35410174950039552

[1, 15, 80, 961, 2802, 52800, 142020, 2347506, 10512320, 96837120, 329849040, 8619170560, 16148168402, 221483030400, 1146781040640, 14442767744328, 38774519976900, 813898294809600, 1904350030969680, 35410174950039552]

cp's OEIS Frontend

A102360 a(n) = sigma((7^n - 1)/6), where sigma(n) is the sum of positive divisors of n.

Table of values

List of values