A162923 - cp's OEIS frontend

A162923 Numbers k such that the equation sigma(sigma(x)) = k has no solutions.

n	a(n)
1	2
2	3
3	5
4	6
5	9
6	10
7	11
8	13
9	16
10	17
11	18
12	19
13	20
14	21
15	22
16	23
17	25
18	26
19	27
20	29
21	30
22	31
23	33
24	34
25	35
26	36
27	37
28	38
29	40
30	41
31	43
32	44
33	45
34	46
35	47
36	48
37	49
38	50
39	51
40	52
41	53
42	54
43	55
44	57
45	58
46	59
47	61
48	62
49	64
50	65
51	66
52	67
53	68
54	69
55	70
56	71
57	73
58	74
59	75
60	76
61	77
62	78
63	79
64	81
65	82
66	83
67	85
68	86
69	87
70	88
71	89
72	92
73	93

[2, 3, 5, 6, 9, 10, 11, 13, 16, 17, 18, 19, 20, 21, 22, 23, 25, 26, 27, 29, 30, 31, 33, 34, 35, 36, 37, 38, 40, 41, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 57, 58, 59, 61, 62, 64, 65, 66, 67, 68, 69, 70, 71, 73, 74, 75, 76, 77, 78, 79, 81, 82, 83, 85, 86, 87, 88, 89, 92, 93]

cp's OEIS Frontend

A162923 Numbers k such that the equation sigma(sigma(x)) = k has no solutions.

Table of values

List of values

n	a(n)
1	2
2	3
3	5
4	6
5	9
6	10
7	11
8	13
9	16
10	17
11	18
12	19
13	20
14	21
15	22
16	23
17	25
18	26
19	27
20	29
21	30
22	31
23	33
24	34
25	35
26	36
27	37
28	38
29	40
30	41
31	43
32	44
33	45
34	46
35	47
36	48
37	49
38	50
39	51
40	52
41	53
42	54
43	55
44	57
45	58
46	59
47	61
48	62
49	64
50	65
51	66
52	67
53	68
54	69
55	70
56	71
57	73
58	74
59	75
60	76
61	77
62	78
63	79
64	81
65	82
66	83
67	85
68	86
69	87
70	88
71	89
72	92
73	93

n	a(n)
1	2
2	3
3	5
4	6
5	9
6	10
7	11
8	13
9	16
10	17
11	18
12	19
13	20
14	21
15	22
16	23
17	25
18	26
19	27
20	29
21	30
22	31
23	33
24	34
25	35
26	36
27	37
28	38
29	40
30	41
31	43
32	44
33	45
34	46
35	47
36	48
37	49
38	50
39	51
40	52
41	53
42	54
43	55
44	57
45	58
46	59
47	61
48	62
49	64
50	65
51	66
52	67
53	68
54	69
55	70
56	71
57	73
58	74
59	75
60	76
61	77
62	78
63	79
64	81
65	82
66	83
67	85
68	86
69	87
70	88
71	89
72	92
73	93

n	a(n)
1	2
2	3
3	5
4	6
5	9
6	10
7	11
8	13
9	16
10	17
11	18
12	19
13	20
14	21
15	22
16	23
17	25
18	26
19	27
20	29
21	30
22	31
23	33
24	34
25	35
26	36
27	37
28	38
29	40
30	41
31	43
32	44
33	45
34	46
35	47
36	48
37	49
38	50
39	51
40	52
41	53
42	54
43	55
44	57
45	58
46	59
47	61
48	62
49	64
50	65
51	66
52	67
53	68
54	69
55	70
56	71
57	73
58	74
59	75
60	76
61	77
62	78
63	79
64	81
65	82
66	83
67	85
68	86
69	87
70	88
71	89
72	92
73	93