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Averages of twin prime pairs such that p1 * p2 + AverageTwinPrime is prime.
2

%I #14 Sep 08 2022 08:45:40

%S 4,6,30,60,138,180,240,420,618,1050,1608,1698,1788,2268,2310,2730,

%T 3258,3390,3528,3768,4158,4218,4338,4800,5640,5868,6660,6690,6870,

%U 6960,7488,7548,7590,8538,8628,8970,9630,9858,9930,10458,11118,11970,12540,13338

%N Averages of twin prime pairs such that p1 * p2 + AverageTwinPrime is prime.

%H Amiram Eldar, <a href="/A154667/b154667.txt">Table of n, a(n) for n = 1..10000</a>

%e 3*5 + 4 = 19.

%e 5*7 + 6 = 41.

%t lst={};Do[If[PrimeQ[n-1]&&PrimeQ[n+1],If[PrimeQ[(n-1)*(n+1)+n],AppendTo[lst,n]]],{n,8!}];lst

%o (Magma) [p+1:p in PrimesUpTo(14000)|IsPrime(p+2) and IsPrime(p*(p+2)+p+1)]; // _Marius A. Burtea_, Dec 21 2019

%Y Cf. A154666.

%Y A014574 INTERSECT A045546. - _R. J. Mathar_, May 31 2010

%K nonn

%O 1,1

%A _Vladimir Joseph Stephan Orlovsky_, Jan 13 2009