A359167 - cp's OEIS frontend

A359167 Numbers k for which there is an even number of prime factors (when counted with multiplicity) in k*sigma(k), where sigma is the sum of divisors function.

n	a(n)
1	1
2	2
3	7
4	11
5	12
6	14
7	15
8	17
9	19
10	20
11	22
12	24
13	29
14	30
15	31
16	32
17	34
18	36
19	38
20	39
21	40
22	41
23	43
24	45
25	47
26	48
27	49
28	52
29	58
30	62
31	65
32	67
33	69
34	71
35	72
36	75
37	77
38	78
39	79
40	80
41	81
42	82
43	84
44	86
45	90
46	92
47	94
48	97
49	98
50	100
51	101
52	104
53	105
54	107
55	108
56	109
57	111
58	113
59	115
60	117
61	119
62	121
63	127
64	128
65	130
66	132
67	133
68	134
69	135
70	137
71	138

[1, 2, 7, 11, 12, 14, 15, 17, 19, 20, 22, 24, 29, 30, 31, 32, 34, 36, 38, 39, 40, 41, 43, 45, 47, 48, 49, 52, 58, 62, 65, 67, 69, 71, 72, 75, 77, 78, 79, 80, 81, 82, 84, 86, 90, 92, 94, 97, 98, 100, 101, 104, 105, 107, 108, 109, 111, 113, 115, 117, 119, 121, 127, 128, 130, 132, 133, 134, 135, 137, 138]

cp's OEIS Frontend

A359167 Numbers k for which there is an even number of prime factors (when counted with multiplicity) in k*sigma(k), where sigma is the sum of divisors function.

Table of values

List of values

n	a(n)
1	1
2	2
3	7
4	11
5	12
6	14
7	15
8	17
9	19
10	20
11	22
12	24
13	29
14	30
15	31
16	32
17	34
18	36
19	38
20	39
21	40
22	41
23	43
24	45
25	47
26	48
27	49
28	52
29	58
30	62
31	65
32	67
33	69
34	71
35	72
36	75
37	77
38	78
39	79
40	80
41	81
42	82
43	84
44	86
45	90
46	92
47	94
48	97
49	98
50	100
51	101
52	104
53	105
54	107
55	108
56	109
57	111
58	113
59	115
60	117
61	119
62	121
63	127
64	128
65	130
66	132
67	133
68	134
69	135
70	137
71	138

n	a(n)
1	1
2	2
3	7
4	11
5	12
6	14
7	15
8	17
9	19
10	20
11	22
12	24
13	29
14	30
15	31
16	32
17	34
18	36
19	38
20	39
21	40
22	41
23	43
24	45
25	47
26	48
27	49
28	52
29	58
30	62
31	65
32	67
33	69
34	71
35	72
36	75
37	77
38	78
39	79
40	80
41	81
42	82
43	84
44	86
45	90
46	92
47	94
48	97
49	98
50	100
51	101
52	104
53	105
54	107
55	108
56	109
57	111
58	113
59	115
60	117
61	119
62	121
63	127
64	128
65	130
66	132
67	133
68	134
69	135
70	137
71	138

n	a(n)
1	1
2	2
3	7
4	11
5	12
6	14
7	15
8	17
9	19
10	20
11	22
12	24
13	29
14	30
15	31
16	32
17	34
18	36
19	38
20	39
21	40
22	41
23	43
24	45
25	47
26	48
27	49
28	52
29	58
30	62
31	65
32	67
33	69
34	71
35	72
36	75
37	77
38	78
39	79
40	80
41	81
42	82
43	84
44	86
45	90
46	92
47	94
48	97
49	98
50	100
51	101
52	104
53	105
54	107
55	108
56	109
57	111
58	113
59	115
60	117
61	119
62	121
63	127
64	128
65	130
66	132
67	133
68	134
69	135
70	137
71	138