A358082 - cp's OEIS frontend

A358082 a(1) = 1, a(2) = 2; for n > 2, a(n) is the smallest positive number not occurring earlier that shares a factor with Sum_{k=1..n-1} sigma(a(k)).

n	a(n)
1	1
2	2
3	4
4	11
5	23
6	47
7	5
8	101
9	7
10	211
11	3
12	14
13	22
14	487
15	6
16	9
17	8
18	10
19	1033
20	12
21	15
22	13
23	18
24	16
25	2203
26	21
27	46
28	26
29	29
30	4583
31	89
32	9257
33	20
34	28
35	35
36	18661
37	24
38	17
39	27
40	37441
41	30
42	19
43	25
44	32
45	33
46	36
47	34
48	38
49	39
50	40
51	42
52	44
53	45
54	48
55	37
56	31
57	50
58	49
59	52
60	54
61	56
62	58
63	60
64	62
65	63
66	51
67	57
68	64
69	55
70	66
71	69
72	72

[1, 2, 4, 11, 23, 47, 5, 101, 7, 211, 3, 14, 22, 487, 6, 9, 8, 10, 1033, 12, 15, 13, 18, 16, 2203, 21, 46, 26, 29, 4583, 89, 9257, 20, 28, 35, 18661, 24, 17, 27, 37441, 30, 19, 25, 32, 33, 36, 34, 38, 39, 40, 42, 44, 45, 48, 37, 31, 50, 49, 52, 54, 56, 58, 60, 62, 63, 51, 57, 64, 55, 66, 69, 72]

cp's OEIS Frontend

A358082 a(1) = 1, a(2) = 2; for n > 2, a(n) is the smallest positive number not occurring earlier that shares a factor with Sum_{k=1..n-1} sigma(a(k)).

Table of values

List of values