A356873 - cp's OEIS frontend

A356873 a(n) is the smallest number k such that 2^k+1 has at least n distinct prime factors.

n	a(n)
1	0
2	5
3	14
4	18
5	30
6	42
7	78
8	78
9	78
10	90
11	150
12	150
13	210
14	210
15	234
16	234
17	270
18	390
19	390
20	390
21	390
22	450
23	510
24	630
25	630
26	630
27	810
28	810
29	810
30	966
31	966
32	1170
33	1170
34	1170
35	1170
36	1170
37	1170
38	1170

[0, 5, 14, 18, 30, 42, 78, 78, 78, 90, 150, 150, 210, 210, 234, 234, 270, 390, 390, 390, 390, 450, 510, 630, 630, 630, 810, 810, 810, 966, 966, 1170, 1170, 1170, 1170, 1170, 1170, 1170]

cp's OEIS Frontend

A356873 a(n) is the smallest number k such that 2^k+1 has at least n distinct prime factors.

Table of values

List of values