A385958 - cp's OEIS frontend

A385958 a(n) is the largest prime p such that b(n) = b(n-1)*(p+1)/(p-1) is an integer (A385959), where b(0) = 1.

n	a(n)
1	3
2	5
3	7
4	5
5	13
6	3
7	29
8	31
9	17
10	37
11	3
12	5
13	7
14	5
15	229
16	47
17	241
18	23
19	89
20	271
21	137
22	277
23	3
24	557
25	19
26	311
27	313
28	5
29	7
30	5
31	13
32	3
33	4397
34	7
35	5
36	13
37	3
38	29
39	21991
40	5
41	13
42	3
43	29
44	82471
45	677
46	733
47	227
48	27893
49	19
50	11
51	111577
52	3
53	5
54	283
55	5
56	505663
57	15803

[3, 5, 7, 5, 13, 3, 29, 31, 17, 37, 3, 5, 7, 5, 229, 47, 241, 23, 89, 271, 137, 277, 3, 557, 19, 311, 313, 5, 7, 5, 13, 3, 4397, 7, 5, 13, 3, 29, 21991, 5, 13, 3, 29, 82471, 677, 733, 227, 27893, 19, 11, 111577, 3, 5, 283, 5, 505663, 15803]

cp's OEIS Frontend

A385958 a(n) is the largest prime p such that b(n) = b(n-1)*(p+1)/(p-1) is an integer (A385959), where b(0) = 1.

Table of values

List of values