%I A023273
%S A023273 2,5,47,67,97,137,197,277,307,607,617,1307,1427,2857,5717,6047,6217,6257,
%T A023273 6997,9377,9787,9967,11197,12097,13297,13997,14347,16057,18757,18947,
%U A023273 20887,21517,21587,21757,24197,26227,28097,28447,32117,33767,34367,35117
%N A023273 Numbers n such that n remains prime through 3 iterations of function 
               f(x) = 2x + 3.
%Y A023273 Sequence in context: A005166 A121621 A119715 this_sequence A041729 A078665 
               A163666
%Y A023273 Adjacent sequences: A023270 A023271 A023272 this_sequence A023274 A023275 
               A023276
%K A023273 nonn
%O A023273 1,1
%A A023273 David W. Wilson (davidwwilson(AT)comcast.net)