%I A023224
%S A023224 7,19,37,61,79,97,139,151,157,211,229,271,307,349,379,457,487,547,571,
%T A023224 601,607,619,631,709,751,757,769,829,877,907,937,997,1021,1069,1117,1129,
%U A023224 1237,1249,1291,1327,1429,1447,1471,1489,1549,1567,1579,1621,1627,1699
%N A023224 Numbers n such that n and 7n + 4 both prime.
%t A023224 lst={}; Do[p=Prime[n]; If[PrimeQ[7*p+4],AppendTo[lst,p]],{n,6!}]; lst 
               [From Vladimir Orlovsky (4vladimir(AT)gmail.com), Aug 16 2009]
%Y A023224 Sequence in context: A038847 A130056 A136057 this_sequence A113743 A003215 
               A133323
%Y A023224 Adjacent sequences: A023221 A023222 A023223 this_sequence A023225 A023226 
               A023227
%K A023224 nonn
%O A023224 1,1
%A A023224 David W. Wilson (davidwwilson(AT)comcast.net)