A174161 - cp's OEIS frontend

A174161 a(1) = 2. Let k >= 1 be the minimal integer such that 2ka(n-1) - 1 has at least one prime divisor which is not already in the sequence. Then a(n) is the smallest such divisor.

n	a(n)
1	2
2	3
3	5
4	19
5	37
6	73
7	29
8	23
9	7
10	13
11	17
12	11
13	43
14	257
15	79
16	157
17	313
18	139
19	277
20	41
21	163
22	31
23	61
24	487
25	59
26	47
27	281
28	1123
29	449
30	359
31	239
32	53
33	211
34	421
35	101
36	67
37	89
38	71
39	283
40	113
41	677
42	2707
43	5413
44	433
45	173
46	691
47	1381
48	251
49	167
50	1669
51	5563
52	7417
53	44501
54	431
55	1723
56	2297

[2, 3, 5, 19, 37, 73, 29, 23, 7, 13, 17, 11, 43, 257, 79, 157, 313, 139, 277, 41, 163, 31, 61, 487, 59, 47, 281, 1123, 449, 359, 239, 53, 211, 421, 101, 67, 89, 71, 283, 113, 677, 2707, 5413, 433, 173, 691, 1381, 251, 167, 1669, 5563, 7417, 44501, 431, 1723, 2297]

cp's OEIS Frontend

A174161 a(1) = 2. Let k >= 1 be the minimal integer such that 2ka(n-1) - 1 has at least one prime divisor which is not already in the sequence. Then a(n) is the smallest such divisor.

Table of values

List of values

cp's OEIS Frontend

A174161 a(1) = 2. Let k >= 1 be the minimal integer such that 2*k*a(n-1) - 1 has at least one prime divisor which is not already in the sequence. Then a(n) is the smallest such divisor.

Table of values

List of values

A174161 a(1) = 2. Let k >= 1 be the minimal integer such that 2ka(n-1) - 1 has at least one prime divisor which is not already in the sequence. Then a(n) is the smallest such divisor.