A349756 - cp's OEIS frontend

A349756 Numbers k such that the odd part of sigma(k) is equal to gcd(sigma(k), A003961(k)), where A003961 is fully multiplicative with a(p) = nextprime(p), and sigma is the sum of divisors function.

n	a(n)
1	1
2	2
3	3
4	6
5	7
6	14
7	20
8	21
9	24
10	27
11	31
12	42
13	54
14	57
15	60
16	62
17	93
18	114
19	120
20	127
21	140
22	160
23	168
24	186
25	189
26	216
27	217
28	220
29	237
30	254
31	264
32	301
33	378
34	381
35	399
36	408
37	420
38	434
39	460
40	474
41	480
42	513
43	540
44	552
45	602
46	620
47	651
48	660
49	744
50	762
51	792
52	798
53	837
54	840
55	889
56	903
57	940
58	1026
59	1080
60	1120
61	1128
62	1140
63	1302
64	1320
65	1380
66	1392
67	1512

[1, 2, 3, 6, 7, 14, 20, 21, 24, 27, 31, 42, 54, 57, 60, 62, 93, 114, 120, 127, 140, 160, 168, 186, 189, 216, 217, 220, 237, 254, 264, 301, 378, 381, 399, 408, 420, 434, 460, 474, 480, 513, 540, 552, 602, 620, 651, 660, 744, 762, 792, 798, 837, 840, 889, 903, 940, 1026, 1080, 1120, 1128, 1140, 1302, 1320, 1380, 1392, 1512]

cp's OEIS Frontend

A349756 Numbers k such that the odd part of sigma(k) is equal to gcd(sigma(k), A003961(k)), where A003961 is fully multiplicative with a(p) = nextprime(p), and sigma is the sum of divisors function.

Table of values

List of values