A173232 - OEIS

A173232

Numbers k such that k and k+2 are both members of A002822.

1, 3, 5, 10, 23, 30, 38, 45, 70, 135, 170, 175, 213, 215, 268, 355, 465, 560, 588, 653, 703, 705, 710, 773, 798, 835, 940, 978, 1115, 1130, 1158, 1258, 1370, 1500, 1570, 1843, 1860, 2040, 2280, 2285, 2333, 2425, 2985, 3008, 3020, 3598, 3600, 3838, 4375, 4450, 4480

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,2

LINKS

Table of n, a(n) for n=1..51.

EXAMPLE

a(1)=1 because 1 and 3 are both in A002822.

PROG

(PARI) isokp(n) = isprime(6*n-1) && isprime(6*n+1);

isok(k) = isokp(k) && isokp(k+2); \\ Michel Marcus, May 15 2020

CROSSREFS

Cf. A002822, A173233.