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Primes of the form 2(p+q) + 1, p and q prime.
1

%I #5 Oct 12 2019 15:36:18

%S 11,13,17,19,29,31,37,41,43,53,61,67,73,79,89,97,101,109,113,127,137,

%T 139,149,151,157,163,173,181,193,197,199,211,223,229,233,241,257,269,

%U 277,281,283,293,307,313,317,331,337,349,353,367,373,389,397,401,409

%N Primes of the form 2(p+q) + 1, p and q prime.

%t Select[2#+1&/@Union[Total/@Tuples[Prime[Range[50]],2]],PrimeQ] (* _Harvey P. Dale_, Oct 12 2019 *)

%o (PARI) {z=410;v=[];p=2;while(2*(p+2)+1<z,q=2;while((n=2*(p+q)+1)<z,if(isprime(n),v=concat(v,n));q=nextprime(q+1));p=nextprime(p+1));v=vecsort(v);m=0;for(j=1,length(v),if(m<v[j],m=v[j];print1(m,",")))} - Klaus Brockhaus, Sep 19 2004

%K nonn

%O 1,1

%A _Giovanni Teofilatto_, Sep 18 2004

%E Edited and extended by _Klaus Brockhaus_, Sep 19 2004