A338790 - cp's OEIS frontend

A338790 a(n) = rad(n)^2 - sigma(n), where rad(n) is the squarefree kernel of n (A007947) and sigma(n) is the sum of divisors of n (A000203).

n	a(n)
1	0
2	1
3	5
4	-3
5	19
6	24
7	41
8	-11
9	-4
10	82
11	109
12	8
13	155
14	172
15	201
16	-27
17	271
18	-3
19	341
20	58
21	409
22	448
23	505
24	-24
25	-6
26	634
27	-31
28	140
29	811
30	828
31	929
32	-59
33	1041
34	1102
35	1177
36	-55
37	1331
38	1384
39	1465
40	10
41	1639
42	1668
43	1805
44	400
45	147
46	2044
47	2161
48	-88
49	-8
50	7
51	2529
52	578
53	2755
54	-84
55	2953

[0, 1, 5, -3, 19, 24, 41, -11, -4, 82, 109, 8, 155, 172, 201, -27, 271, -3, 341, 58, 409, 448, 505, -24, -6, 634, -31, 140, 811, 828, 929, -59, 1041, 1102, 1177, -55, 1331, 1384, 1465, 10, 1639, 1668, 1805, 400, 147, 2044, 2161, -88, -8, 7, 2529, 578, 2755, -84, 2953]

cp's OEIS Frontend

A338790 a(n) = rad(n)^2 - sigma(n), where rad(n) is the squarefree kernel of n (A007947) and sigma(n) is the sum of divisors of n (A000203).

Table of values

List of values