A248793 - cp's OEIS frontend

A248793 Sigma(n) - 1 for n such that sigma(n) - 1 is prime.

n	a(n)
1	2
2	3
3	5
4	11
5	7
6	17
7	11
8	13
9	23
10	23
11	17
12	19
13	41
14	31
15	23
16	59
17	41
18	29
19	71
20	31
21	47
22	53
23	47
24	37
25	59
26	89
27	41
28	43
29	83
30	71
31	47
32	71
33	97
34	53
35	71
36	79
37	89
38	59
39	167
40	61
41	103
42	83
43	67
44	71
45	73
46	113
47	139
48	167
49	79
50	83
51	223
52	107
53	131
54	179
55	89
56	233
57	167
58	127
59	251
60	97
61	101
62	103

[2, 3, 5, 11, 7, 17, 11, 13, 23, 23, 17, 19, 41, 31, 23, 59, 41, 29, 71, 31, 47, 53, 47, 37, 59, 89, 41, 43, 83, 71, 47, 71, 97, 53, 71, 79, 89, 59, 167, 61, 103, 83, 67, 71, 73, 113, 139, 167, 79, 83, 223, 107, 131, 179, 89, 233, 167, 127, 251, 97, 101, 103]

cp's OEIS Frontend

A248793 Sigma(n) - 1 for n such that sigma(n) - 1 is prime.

Table of values

List of values

n	a(n)
1	2
2	3
3	5
4	11
5	7
6	17
7	11
8	13
9	23
10	23
11	17
12	19
13	41
14	31
15	23
16	59
17	41
18	29
19	71
20	31
21	47
22	53
23	47
24	37
25	59
26	89
27	41
28	43
29	83
30	71
31	47
32	71
33	97
34	53
35	71
36	79
37	89
38	59
39	167
40	61
41	103
42	83
43	67
44	71
45	73
46	113
47	139
48	167
49	79
50	83
51	223
52	107
53	131
54	179
55	89
56	233
57	167
58	127
59	251
60	97
61	101
62	103

n	a(n)
1	2
2	3
3	5
4	11
5	7
6	17
7	11
8	13
9	23
10	23
11	17
12	19
13	41
14	31
15	23
16	59
17	41
18	29
19	71
20	31
21	47
22	53
23	47
24	37
25	59
26	89
27	41
28	43
29	83
30	71
31	47
32	71
33	97
34	53
35	71
36	79
37	89
38	59
39	167
40	61
41	103
42	83
43	67
44	71
45	73
46	113
47	139
48	167
49	79
50	83
51	223
52	107
53	131
54	179
55	89
56	233
57	167
58	127
59	251
60	97
61	101
62	103

n	a(n)
1	2
2	3
3	5
4	11
5	7
6	17
7	11
8	13
9	23
10	23
11	17
12	19
13	41
14	31
15	23
16	59
17	41
18	29
19	71
20	31
21	47
22	53
23	47
24	37
25	59
26	89
27	41
28	43
29	83
30	71
31	47
32	71
33	97
34	53
35	71
36	79
37	89
38	59
39	167
40	61
41	103
42	83
43	67
44	71
45	73
46	113
47	139
48	167
49	79
50	83
51	223
52	107
53	131
54	179
55	89
56	233
57	167
58	127
59	251
60	97
61	101
62	103