Search: id:A157345
Results 1-1 of 1 results found.

%I A157345
%S A157345 91,119,133,217,221,247,259,301,323,329,403,413,427,469,481,497,511,527,
%T A157345 553,559,589,611,629,679,703,707,721,731,749,763,767,793,799,817,871,
%U A157345 889,893,923,949,959,973,1003,1027,1037,1043,1057,1099,1121,1139,1141
%N A157345 Numbers (semiprimes) that are the product of two distinct not-Sophie 
               Germain primes.
%C A157345 91=7*13 7 and 13 are not-Sophie Germain primes, ...
%t A157345 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
%Y A157345 Cf. A001358, A005384, A111206, A157342, A006881, A157344
%Y A157345 Sequence in context: A020223 A161945 A140389 this_sequence A092125 A005935 
               A020307
%Y A157345 Adjacent sequences: A157342 A157343 A157344 this_sequence A157346 A157347 
               A157348
%K A157345 nonn
%O A157345 1,1
%A A157345 Vladmir Orlovsky (4vladimir(AT)gmail.com), Feb 27 2009

Search completed in 0.001 seconds