OFFSET
0,1
LINKS
Jianing Song, Table of n, a(n) for n = 0..10000
EXAMPLE
There are 14 primes <= 6*16+5 = 101 that are congruent to 2 modulo 3, namely 2, 5, 11, 17, 23, 29, 41, 47, 53, 59, 71, 83, 89, 101, so a(16) = 14.
PROG
(PARI) a(n) = sum(i=1, 6*n+5, isprime(i) && (i%3==2))
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Jianing Song, Apr 28 2021
STATUS
approved