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%I #17 Aug 15 2017 17:38:40
%S 3,13,31,43,73,109,139,151,181,193,211,223,229,283,349,379,409,421,
%T 463,523,601,619,691,769,823,853,1021,1033,1069,1153,1231,1279,1303,
%U 1453,1459,1471,1531,1663,1693,1723,1741,1783,1831,1873,1933,2029,2131,2251,2269,2293,2593,2671,2749,2791
%N Primes p such that 52*p + 1 is prime.
%C Or, primes in A248221. Subsequence of A248221. Note that a(1..6) coincide with A171517(1..6).
%H Jens Kruse Andersen, <a href="/A248368/b248368.txt">Table of n, a(n) for n = 1..10000</a>
%p A248368:=n->`if`(isprime(52*n+1) and isprime(n), n, NULL): seq(A248368(n), n=1..4000); # _Wesley Ivan Hurt_, Oct 05 2014
%t s = {}; Do[If[PrimeQ[1 + 52*(p = Prime[n])], AppendTo[s, p]], {n, 500}]; s
%t Select[Prime[Range[500]],PrimeQ[52#+1]&] (* _Harvey P. Dale_, Aug 15 2017 *)
%o (PARI)
%o forprime(p=1,10^4,if(isprime(52*p+1),print1(p,", "))) \\ _Derek Orr_, Oct 05 2014
%Y Cf. A033210, A142508, A171517, A248221.
%K nonn,easy
%O 1,1
%A _Zak Seidov_, Oct 05 2014
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