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%I #4 May 02 2023 15:20:16
%S 29,89,419,509,659,1259,1289,1319,1949,2099,2309,2339,2609,2939,3989,
%T 4049,6089,6599,7559,8609,9239,9539,10709,12659,12899,13469,13499,
%U 18119,20399,21089,21269,21419,22469,23369,26669,27539,28559,30059,30449
%N Primes of the form : (p-n)/(n+1)=prime and (n+1)*p+n=prime. n=4.
%C This is the general form : (p-n)/(n+1)=primeand(n+1)*p+n=prime; 'Safe' primes and'Sophie Germain' primes just one part of this general form; If n=1 then we got'Safe' primes and'Sophie Germain' primes.
%t lst={};n=4;Do[p=Prime[k];If[PrimeQ[(p-n)/(n+1)]&&PrimeQ[(n+1)*p+n],AppendTo[lst,p]],{k,7!}];lst
%Y Cf. A059455, A152292, A152293.
%K nonn
%O 1,1
%A _Vladimir Joseph Stephan Orlovsky_, Dec 02 2008
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