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Primes p such that 2*p+3234846615 is also a prime number.
1

%I #10 Sep 08 2022 08:45:45

%S 31,43,71,73,89,107,139,179,211,223,241,269,271,281,293,311,317,337,

%T 379,383,389,419,443,449,467,503,563,569,587,607,647,653,727,739,743,

%U 757,761,811,839,857,863,881,941,967,977,991,1019,1021,1049,1061,1069,1087

%N Primes p such that 2*p+3234846615 is also a prime number.

%C The large constant is constructed as 3*5*7*11*13*17*19*23*29 = 3234846615.

%H Vincenzo Librandi, <a href="/A161615/b161615.txt">Table of n, a(n) for n = 1..1000</a>

%e The prime 31 is in the sequence because 2*31 + 3234846615 = 3234846677 is also prime.

%t a=3*5*7*11*13*17*19*23*29;c=0;lst={};Do[p=Prime[n];If[PrimeQ[2*p+a],AppendTo[lst, p],c++ ],{n,6!}];lst

%t With[{c=Times@@Prime[Range[2,10]]},Select[Prime[Range[200]], PrimeQ[ 2#+c]&]] (* _Harvey P. Dale_, Dec 30 2012 *)

%t Select[Prime[Range[300]], PrimeQ[2 # + 3234846615]&] (* _Vincenzo Librandi_, Apr 15 2013 *)

%o (Magma) [p: p in PrimesUpTo(1100) | IsPrime(2*p+3234846615)]; // _Vincenzo Librandi_, Apr 15 2013

%K nonn,less

%O 1,1

%A _Vladimir Joseph Stephan Orlovsky_, Jun 14 2009

%E Definition reworded by _R. J. Mathar_, Oct 02 2009