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Lesser of twin primes p1 and p2 such that 2*p1+p2 is a prime number.
10

%I #9 Aug 13 2024 11:52:12

%S 3,5,17,29,59,149,197,227,239,269,419,569,659,1277,1427,1487,1667,

%T 1949,2087,2129,2267,2339,2549,2789,2999,3359,3389,3929,4049,4157,

%U 4217,4229,4517,4637,5099,5417,5477,6089,6197,6299,6359,6569,6659,6827,6959,7127

%N Lesser of twin primes p1 and p2 such that 2*p1+p2 is a prime number.

%C (p1, p2=p1+2) is a pair of twin primes.

%H Harvey P. Dale, <a href="/A174913/b174913.txt">Table of n, a(n) for n = 1..10000</a>

%t lst={};Do[p1=Prime[n];p2=p1+2;If[PrimeQ[p2]&&PrimeQ[2*p1+p2],AppendTo[lst,p1]],{n,7!}];lst

%t Transpose[Select[Partition[Prime[Range[1000]],2,1],#[[2]]-#[[1]] == 2 && PrimeQ[ 2#[[1]]+ #[[2]]]&]][[1]] (* _Harvey P. Dale_, Apr 09 2012 *)

%Y Cf. A001359

%K nonn

%O 1,1

%A _Vladimir Joseph Stephan Orlovsky_, Apr 02 2010

%E Definition edited by _Harvey P. Dale_, Aug 13 2024