A351554 - cp's OEIS frontend

A351554 Numbers k such that there are no odd prime factors p of sigma(k) such that p does not divide A003961(k) and the valuation(k, p) is different from valuation(sigma(k), p), 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	10
7	14
8	15
9	20
10	21
11	22
12	24
13	27
14	28
15	30
16	31
17	33
18	34
19	40
20	42
21	46
22	54
23	57
24	60
25	62
26	66
27	69
28	70
29	84
30	87
31	91
32	93
33	94
34	102
35	105
36	106
37	110
38	114
39	120
40	127
41	130
42	138
43	140
44	141
45	142
46	154
47	160
48	168
49	170
50	174
51	177
52	182
53	186
54	189
55	190
56	195
57	198
58	210
59	214
60	216
61	217
62	220
63	224
64	230
65	231
66	237
67	238
68	254
69	260
70	264
71	270
72	273

[1, 2, 3, 6, 7, 10, 14, 15, 20, 21, 22, 24, 27, 28, 30, 31, 33, 34, 40, 42, 46, 54, 57, 60, 62, 66, 69, 70, 84, 87, 91, 93, 94, 102, 105, 106, 110, 114, 120, 127, 130, 138, 140, 141, 142, 154, 160, 168, 170, 174, 177, 182, 186, 189, 190, 195, 198, 210, 214, 216, 217, 220, 224, 230, 231, 237, 238, 254, 260, 264, 270, 273]

cp's OEIS Frontend

A351554 Numbers k such that there are no odd prime factors p of sigma(k) such that p does not divide A003961(k) and the valuation(k, p) is different from valuation(sigma(k), p), where A003961 is fully multiplicative with a(p) = nextprime(p), and sigma is the sum of divisors function.

Table of values

List of values

n	a(n)
1	1
2	2
3	3
4	6
5	7
6	10
7	14
8	15
9	20
10	21
11	22
12	24
13	27
14	28
15	30
16	31
17	33
18	34
19	40
20	42
21	46
22	54
23	57
24	60
25	62
26	66
27	69
28	70
29	84
30	87
31	91
32	93
33	94
34	102
35	105
36	106
37	110
38	114
39	120
40	127
41	130
42	138
43	140
44	141
45	142
46	154
47	160
48	168
49	170
50	174
51	177
52	182
53	186
54	189
55	190
56	195
57	198
58	210
59	214
60	216
61	217
62	220
63	224
64	230
65	231
66	237
67	238
68	254
69	260
70	264
71	270
72	273

n	a(n)
1	1
2	2
3	3
4	6
5	7
6	10
7	14
8	15
9	20
10	21
11	22
12	24
13	27
14	28
15	30
16	31
17	33
18	34
19	40
20	42
21	46
22	54
23	57
24	60
25	62
26	66
27	69
28	70
29	84
30	87
31	91
32	93
33	94
34	102
35	105
36	106
37	110
38	114
39	120
40	127
41	130
42	138
43	140
44	141
45	142
46	154
47	160
48	168
49	170
50	174
51	177
52	182
53	186
54	189
55	190
56	195
57	198
58	210
59	214
60	216
61	217
62	220
63	224
64	230
65	231
66	237
67	238
68	254
69	260
70	264
71	270
72	273

n	a(n)
1	1
2	2
3	3
4	6
5	7
6	10
7	14
8	15
9	20
10	21
11	22
12	24
13	27
14	28
15	30
16	31
17	33
18	34
19	40
20	42
21	46
22	54
23	57
24	60
25	62
26	66
27	69
28	70
29	84
30	87
31	91
32	93
33	94
34	102
35	105
36	106
37	110
38	114
39	120
40	127
41	130
42	138
43	140
44	141
45	142
46	154
47	160
48	168
49	170
50	174
51	177
52	182
53	186
54	189
55	190
56	195
57	198
58	210
59	214
60	216
61	217
62	220
63	224
64	230
65	231
66	237
67	238
68	254
69	260
70	264
71	270
72	273