A349175 - cp's OEIS frontend

A349175 Odd numbers k for which gcd(k, A003961(k)) <> gcd(sigma(k), A003961(k)), where A003961(n) is fully multiplicative with a(prime(k)) = prime(k+1), and sigma is the sum of divisors function.

n	a(n)
1	15
2	27
3	35
4	45
5	57
6	65
7	75
8	77
9	87
10	99
11	105
12	143
13	165
14	171
15	175
16	177
17	189
18	195
19	205
20	221
21	225
22	231
23	237
24	245
25	255
26	261
27	267
28	297
29	301
30	315
31	323
32	325
33	327
34	345
35	351
36	375
37	385
38	399
39	405
40	415
41	417
42	429
43	437
44	447
45	459
46	465
47	485
48	495
49	513
50	525
51	531
52	537
53	539
54	555
55	567
56	585
57	595
58	597
59	605
60	609
61	615
62	621
63	627
64	629
65	645

[15, 27, 35, 45, 57, 65, 75, 77, 87, 99, 105, 143, 165, 171, 175, 177, 189, 195, 205, 221, 225, 231, 237, 245, 255, 261, 267, 297, 301, 315, 323, 325, 327, 345, 351, 375, 385, 399, 405, 415, 417, 429, 437, 447, 459, 465, 485, 495, 513, 525, 531, 537, 539, 555, 567, 585, 595, 597, 605, 609, 615, 621, 627, 629, 645]

cp's OEIS Frontend

A349175 Odd numbers k for which gcd(k, A003961(k)) <> gcd(sigma(k), A003961(k)), where A003961(n) is fully multiplicative with a(prime(k)) = prime(k+1), and sigma is the sum of divisors function.

Table of values

List of values

n	a(n)
1	15
2	27
3	35
4	45
5	57
6	65
7	75
8	77
9	87
10	99
11	105
12	143
13	165
14	171
15	175
16	177
17	189
18	195
19	205
20	221
21	225
22	231
23	237
24	245
25	255
26	261
27	267
28	297
29	301
30	315
31	323
32	325
33	327
34	345
35	351
36	375
37	385
38	399
39	405
40	415
41	417
42	429
43	437
44	447
45	459
46	465
47	485
48	495
49	513
50	525
51	531
52	537
53	539
54	555
55	567
56	585
57	595
58	597
59	605
60	609
61	615
62	621
63	627
64	629
65	645

n	a(n)
1	15
2	27
3	35
4	45
5	57
6	65
7	75
8	77
9	87
10	99
11	105
12	143
13	165
14	171
15	175
16	177
17	189
18	195
19	205
20	221
21	225
22	231
23	237
24	245
25	255
26	261
27	267
28	297
29	301
30	315
31	323
32	325
33	327
34	345
35	351
36	375
37	385
38	399
39	405
40	415
41	417
42	429
43	437
44	447
45	459
46	465
47	485
48	495
49	513
50	525
51	531
52	537
53	539
54	555
55	567
56	585
57	595
58	597
59	605
60	609
61	615
62	621
63	627
64	629
65	645

n	a(n)
1	15
2	27
3	35
4	45
5	57
6	65
7	75
8	77
9	87
10	99
11	105
12	143
13	165
14	171
15	175
16	177
17	189
18	195
19	205
20	221
21	225
22	231
23	237
24	245
25	255
26	261
27	267
28	297
29	301
30	315
31	323
32	325
33	327
34	345
35	351
36	375
37	385
38	399
39	405
40	415
41	417
42	429
43	437
44	447
45	459
46	465
47	485
48	495
49	513
50	525
51	531
52	537
53	539
54	555
55	567
56	585
57	595
58	597
59	605
60	609
61	615
62	621
63	627
64	629
65	645