OFFSET
1,1
COMMENTS
Positions of a(n) in A165218: 16, 29, 33, 74, 78, 105, 130, 333, 520, 547, 572, 716, 740, 820, 832, 865, 975.
The first primes such that t^2+4 is also prime are 93738231893, 2365771484804813, 4185535280578373, 4658429282719973, 7706774555568173, 7711174427503853, 25756066576859093.
LINKS
Zak Seidov and Charles R Greathouse IV, Table of n, a(n) for n = 1..10000 (first 699 terms from Seidov)
PROG
(PARI) forprime(p=2, 1e7, if(isprime(q=p^2+4) && isprime(r=q^2+4) && isprime(r^2+4), print1(q", "))) \\ Charles R Greathouse IV, Nov 05 2013
CROSSREFS
KEYWORD
nonn
AUTHOR
Zak Seidov, Nov 04 2013
STATUS
approved