A067351 - cp's OEIS frontend

A067351 Numbers k such that sigma(k) + phi(k) has exactly 2 distinct prime divisors.

n	a(n)
1	3
2	5
3	6
4	7
5	10
6	11
7	13
8	16
9	17
10	18
11	19
12	20
13	21
14	22
15	23
16	24
17	25
18	26
19	27
20	28
21	29
22	30
23	31
24	33
25	35
26	37
27	39
28	40
29	41
30	42
31	43
32	44
33	46
34	47
35	49
36	51
37	52
38	53
39	55
40	56
41	57
42	58
43	59
44	60
45	61
46	64
47	66
48	67
49	68
50	71
51	72
52	73
53	75
54	76
55	78
56	79
57	80
58	81
59	82
60	83
61	84
62	85
63	87
64	89
65	91
66	92
67	93
68	95
69	96
70	97

[3, 5, 6, 7, 10, 11, 13, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 33, 35, 37, 39, 40, 41, 42, 43, 44, 46, 47, 49, 51, 52, 53, 55, 56, 57, 58, 59, 60, 61, 64, 66, 67, 68, 71, 72, 73, 75, 76, 78, 79, 80, 81, 82, 83, 84, 85, 87, 89, 91, 92, 93, 95, 96, 97]

cp's OEIS Frontend

A067351 Numbers k such that sigma(k) + phi(k) has exactly 2 distinct prime divisors.

Table of values

List of values

n	a(n)
1	3
2	5
3	6
4	7
5	10
6	11
7	13
8	16
9	17
10	18
11	19
12	20
13	21
14	22
15	23
16	24
17	25
18	26
19	27
20	28
21	29
22	30
23	31
24	33
25	35
26	37
27	39
28	40
29	41
30	42
31	43
32	44
33	46
34	47
35	49
36	51
37	52
38	53
39	55
40	56
41	57
42	58
43	59
44	60
45	61
46	64
47	66
48	67
49	68
50	71
51	72
52	73
53	75
54	76
55	78
56	79
57	80
58	81
59	82
60	83
61	84
62	85
63	87
64	89
65	91
66	92
67	93
68	95
69	96
70	97

n	a(n)
1	3
2	5
3	6
4	7
5	10
6	11
7	13
8	16
9	17
10	18
11	19
12	20
13	21
14	22
15	23
16	24
17	25
18	26
19	27
20	28
21	29
22	30
23	31
24	33
25	35
26	37
27	39
28	40
29	41
30	42
31	43
32	44
33	46
34	47
35	49
36	51
37	52
38	53
39	55
40	56
41	57
42	58
43	59
44	60
45	61
46	64
47	66
48	67
49	68
50	71
51	72
52	73
53	75
54	76
55	78
56	79
57	80
58	81
59	82
60	83
61	84
62	85
63	87
64	89
65	91
66	92
67	93
68	95
69	96
70	97

n	a(n)
1	3
2	5
3	6
4	7
5	10
6	11
7	13
8	16
9	17
10	18
11	19
12	20
13	21
14	22
15	23
16	24
17	25
18	26
19	27
20	28
21	29
22	30
23	31
24	33
25	35
26	37
27	39
28	40
29	41
30	42
31	43
32	44
33	46
34	47
35	49
36	51
37	52
38	53
39	55
40	56
41	57
42	58
43	59
44	60
45	61
46	64
47	66
48	67
49	68
50	71
51	72
52	73
53	75
54	76
55	78
56	79
57	80
58	81
59	82
60	83
61	84
62	85
63	87
64	89
65	91
66	92
67	93
68	95
69	96
70	97