A119584 - cp's OEIS frontend

A119584 a(n) = Sum_{k=1..phi(n)-1} t(n,k)*t(n,k+1), where t(n,k) is the k-th positive integer which is coprime to n and phi(n) is the number of positive integers which are <= n and are coprime to n.

n	a(n)
1	0
2	0
3	2
4	3
5	20
6	5
7	70
8	53
9	121
10	87
11	330
12	117
13	572
14	305
15	507
16	553
17	1360
18	481
19	1938
20	873
21	1586
22	1405
23	3542
24	1241
25	3846
26	2415
27	4006
28	2765
29	7308
30	1875
31	8990
32	4945
33	6828
34	5675
35	9333
36	4525
37	15540
38	8053
39	11567
40	7745
41	21320
42	6047
43	24682
44	12005
45	15244
46	14625

[0, 0, 2, 3, 20, 5, 70, 53, 121, 87, 330, 117, 572, 305, 507, 553, 1360, 481, 1938, 873, 1586, 1405, 3542, 1241, 3846, 2415, 4006, 2765, 7308, 1875, 8990, 4945, 6828, 5675, 9333, 4525, 15540, 8053, 11567, 7745, 21320, 6047, 24682, 12005, 15244, 14625]

cp's OEIS Frontend

A119584 a(n) = Sum_{k=1..phi(n)-1} t(n,k)*t(n,k+1), where t(n,k) is the k-th positive integer which is coprime to n and phi(n) is the number of positive integers which are <= n and are coprime to n.

Table of values

List of values