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%I #15 Feb 02 2018 02:53:45
%S 91,119,133,217,221,247,259,301,323,329,403,413,427,469,481,497,511,
%T 527,553,559,589,611,629,679,703,707,721,731,749,763,767,793,799,817,
%U 871,889,893,923,949,959,973,1003,1027,1037,1043,1057,1099,1121,1139,1141
%N Semiprimes that are the product of two distinct non-Sophie Germain primes.
%C 91 = 7*13; 7 and 13 are not Sophie Germain primes, ...
%H G. C. Greubel, <a href="/A157345/b157345.txt">Table of n, a(n) for n = 1..5000</a>
%t lst={};Do[If[Plus@@Last/@FactorInteger[n]==2,a=Length[First/@FactorInteger[n]];If[a==2,b=First/@FactorInteger[n];c=b[[1]];d=b[[2]];If[ !PrimeQ[2*c+1]&&!PrimeQ[2*d+1],AppendTo[lst,n]]]],{n,7!}];lst
%t With[{nn=50},Take[Union[Times@@@Subsets[Select[Prime[Range[nn]], !PrimeQ[ 2#+1]&],{2}]],nn]] (* _Harvey P. Dale_, May 04 2015 *)
%Y Cf. A001358, A005384, A111206, A157342, A006881, A157344.
%K nonn
%O 1,1
%A _Vladimir Joseph Stephan Orlovsky_, Feb 27 2009
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