%I A023304
%S A023304 13,31,181,541,661,1087,1861,2179,2719,3727,7459,8089,8707,9109,10639,
%T A023304 17341,19333,22501,23293,29287,32797,39847,40387,42703,46591,51613,53101,
%U A023304 56149,56809,57829,59233,80779,87643,89113,89413,91291,93979,94261,98899
%N A023304 Numbers n such that n remains prime through 4 iterations of function 
               f(x) = 2x + 5.
%Y A023304 Sequence in context: A007628 A141837 A104151 this_sequence A159670 A087511 
               A118513
%Y A023304 Adjacent sequences: A023301 A023302 A023303 this_sequence A023305 A023306 
               A023307
%K A023304 nonn
%O A023304 1,1
%A A023304 David W. Wilson (davidwwilson(AT)comcast.net)