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%I #11 Feb 15 2014 13:25:21
%S 2,3,5,8,10,17,18,20,22,26,32,34,42,46,58,70,75,80,87,89,98,104,105,
%T 115,116,121,131,133,142,152,158,167,173,175,177,180,182,189,190,193,
%U 194,218,228,232,237,239,242,267,271,280,282,291,296,326,333,337,339,347
%N Numbers n such that prime(n)^2 + 1 is a semiprime.
%t lst={};Do[If[Plus@@Last/@FactorInteger[Prime[n]^2+1]==2,AppendTo[lst,n]],{n,0,6!}];lst
%t Select[Range[400],PrimeOmega[Prime[#]^2+1]==2&] (* _Harvey P. Dale_, Jun 14 2011 *)
%o (PARI) n=0;forprime(p=2,1e4,n++;if(bigomega(p^2+1)==2,print1(n", "))) \\ _Charles R Greathouse IV_, Jun 14 2011
%K nonn
%O 1,1
%A _Vladimir Joseph Stephan Orlovsky_, Mar 24 2009
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