%I
%S 5,7,9,10,13,15,21,67,75,126,130,147,165,273,286,354,369
%N Numbers n such that 2^(2*n9)9 is prime.
%e 2^(2*79)9=23, 2^(2*99)9=503, 2^(2*109)9=2039, 2^(2*139)9=131063
%t q=9;For[i=q,i<=q,a={};Do[x=2^(2*ni)i;If[PrimeQ[x],AppendTo[a,n]],{n,10^2}];Print["2^(2*n",i,")",i," ",a];i=i+2]
%o (PARI) is(n)=isprime(2^(2*n9)9) \\ _Charles R Greathouse IV_, Jun 13 2017
%K nonn,easy
%O 1,1
%A _Vladimir Joseph Stephan Orlovsky_, May 13 2008
