A328667 - cp's OEIS frontend

A328667 a(n) = Sum_{d divides n} (-1)^(n + 1 + d + n/d) * d^2.

n	a(n)
1	1
2	5
3	10
4	13
5	26
6	50
7	50
8	45
9	91
10	130
11	122
12	130
13	170
14	250
15	260
16	173
17	290
18	455
19	362
20	338
21	500
22	610
23	530
24	450
25	651
26	850
27	820
28	650
29	842
30	1300
31	962
32	685
33	1220
34	1450
35	1300
36	1183
37	1370
38	1810
39	1700
40	1170
41	1682
42	2500
43	1850
44	1586
45	2366
46	2650
47	2210
48	1730
49	2451
50	3255

[1, 5, 10, 13, 26, 50, 50, 45, 91, 130, 122, 130, 170, 250, 260, 173, 290, 455, 362, 338, 500, 610, 530, 450, 651, 850, 820, 650, 842, 1300, 962, 685, 1220, 1450, 1300, 1183, 1370, 1810, 1700, 1170, 1682, 2500, 1850, 1586, 2366, 2650, 2210, 1730, 2451, 3255]

cp's OEIS Frontend

A328667 a(n) = Sum_{d divides n} (-1)^(n + 1 + d + n/d) * d^2.

Table of values

List of values