A154598 - cp's OEIS frontend

A154598 a(n) is the smallest prime p such that p-1 and p+1 both have n prime factors (with multiplicity).

n	a(n)
2	5
3	19
4	89
5	271
6	1889
7	10529
8	75329
9	157951
10	3885569
11	11350529
12	98690561
13	65071999
14	652963841
15	6548416001
16	253401579521
17	160283668481
18	1851643543553
19	3450998226943
20	23114453401601
21	1194899749142527
22	1101483715526657
23	7093521158963201

[5, 19, 89, 271, 1889, 10529, 75329, 157951, 3885569, 11350529, 98690561, 65071999, 652963841, 6548416001, 253401579521, 160283668481, 1851643543553, 3450998226943, 23114453401601, 1194899749142527, 1101483715526657, 7093521158963201]

cp's OEIS Frontend

A154598 a(n) is the smallest prime p such that p-1 and p+1 both have n prime factors (with multiplicity).

Table of values

List of values