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%I #22 Sep 26 2015 15:09:22
%S 25877573,124835933,277455653,2210598293,2970577013,34314969053,
%T 43115615453,90247970573,93738231893,116836126973,153183783773,
%U 720880808213,1818659924933,2068485397733,2258777543933,3449960763653,3645300477293,4501767897173,4670625512573,5238481845533,6812794277693
%N Primes q of the form q = p^2 + 4 (p prime) such that r = q^2 + 4 and t = r^2 + 4 are also prime.
%C Positions of a(n) in A165218: 16, 29, 33, 74, 78, 105, 130, 333, 520, 547, 572, 716, 740, 820, 832, 865, 975.
%C The first primes such that t^2+4 is also prime are 93738231893, 2365771484804813, 4185535280578373, 4658429282719973, 7706774555568173, 7711174427503853, 25756066576859093.
%H Zak Seidov and Charles R Greathouse IV, <a href="/A231120/b231120.txt">Table of n, a(n) for n = 1..10000</a> (first 699 terms from Seidov)
%o (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
%Y Subsequence of A165218.
%K nonn
%O 1,1
%A _Zak Seidov_, Nov 04 2013
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