A347108 - cp's OEIS frontend

A347108 a(n) = Sum_{k=1..n} sigma(k)sigma(2k), where sigma(n) = A000203(n) is the sum of the divisors of n.

n	a(n)
1	3
2	24
3	72
4	177
5	285
6	621
7	813
8	1278
9	1785
10	2541
11	2973
12	4653
13	5241
14	6585
15	8313
16	10266
17	11238
18	14787
19	15987
20	19767
21	22839
22	25863
23	27591
24	35031
25	37914
26	42030
27	46830
28	53550
29	56250
30	68346
31	71418
32	79419
33	86331
34	93135
35	100047
36	117792
37	122124
38	130524
39	139932
40	156672

[3, 24, 72, 177, 285, 621, 813, 1278, 1785, 2541, 2973, 4653, 5241, 6585, 8313, 10266, 11238, 14787, 15987, 19767, 22839, 25863, 27591, 35031, 37914, 42030, 46830, 53550, 56250, 68346, 71418, 79419, 86331, 93135, 100047, 117792, 122124, 130524, 139932, 156672]

cp's OEIS Frontend

A347108 a(n) = Sum_{k=1..n} sigma(k)sigma(2k), where sigma(n) = A000203(n) is the sum of the divisors of n.

Table of values

List of values

cp's OEIS Frontend

A347108 a(n) = Sum_{k=1..n} sigma(k)*sigma(2*k), where sigma(n) = A000203(n) is the sum of the divisors of n.

Table of values

List of values

A347108 a(n) = Sum_{k=1..n} sigma(k)sigma(2k), where sigma(n) = A000203(n) is the sum of the divisors of n.