A185670 - cp's OEIS frontend

A185670 Number of pairs (x,y) with 1 <= x < y <= n with at least one common factor.

n	a(n)
1	0
2	0
3	0
4	1
5	1
6	4
7	4
8	7
9	9
10	14
11	14
12	21
13	21
14	28
15	34
16	41
17	41
18	52
19	52
20	63
21	71
22	82
23	82
24	97
25	101
26	114
27	122
28	137
29	137
30	158
31	158
32	173
33	185
34	202
35	212
36	235
37	235
38	254
39	268
40	291
41	291
42	320
43	320
44	343
45	363
46	386
47	386
48	417
49	423
50	452
51	470
52	497
53	497
54	532
55	546
56	577
57	597
58	626
59	626
60	669
61	669
62	700
63	726
64	757
65	773
66	818
67	818
68	853
69	877
70	922
71	922
72	969
73	969
74	1006
75	1040

[0, 0, 0, 1, 1, 4, 4, 7, 9, 14, 14, 21, 21, 28, 34, 41, 41, 52, 52, 63, 71, 82, 82, 97, 101, 114, 122, 137, 137, 158, 158, 173, 185, 202, 212, 235, 235, 254, 268, 291, 291, 320, 320, 343, 363, 386, 386, 417, 423, 452, 470, 497, 497, 532, 546, 577, 597, 626, 626, 669, 669, 700, 726, 757, 773, 818, 818, 853, 877, 922, 922, 969, 969, 1006, 1040]

cp's OEIS Frontend

A185670 Number of pairs (x,y) with 1 <= x < y <= n with at least one common factor.

Table of values

List of values