A373131 - cp's OEIS frontend

A373131 a(n) = Sum_{1 <= x_1, x_2, x_3 <= n} sigma( ( n/gcd(x_1, x_2, x_3, n) )^2 ).

n	a(n)
1	1
2	50
3	339
4	1786
5	3845
6	16950
7	19495
8	58682
9	85281
10	192250
11	176891
12	605454
13	401869
14	974750
15	1303455
16	1890106
17	1507985
18	4264050
19	2612899
20	6867170
21	6608805
22	8844550
23	6727799
24	19893198
25	12109345
26	20093450
27	20802003
28	34818070
29	21241949
30	65172750
31	29581471
32	60581690

[1, 50, 339, 1786, 3845, 16950, 19495, 58682, 85281, 192250, 176891, 605454, 401869, 974750, 1303455, 1890106, 1507985, 4264050, 2612899, 6867170, 6608805, 8844550, 6727799, 19893198, 12109345, 20093450, 20802003, 34818070, 21241949, 65172750, 29581471, 60581690]

cp's OEIS Frontend

A373131 a(n) = Sum_{1 <= x_1, x_2, x_3 <= n} sigma( ( n/gcd(x_1, x_2, x_3, n) )^2 ).

Table of values

List of values