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Primes p such that (12*p - 1, 12*p + 1) and (18*p - 1, 18*p + 1) are twin primes.
1

%I #17 Sep 08 2022 08:45:33

%S 29,1051,6719,9059,10501,27749,27791,36749,51421,83761,86729,108751,

%T 115249,120049,124139,124529,138629,148861,152839,162091,169009,

%U 176609,178249,178921,202481,203141,209621,228199,232681,244411,302779,309259

%N Primes p such that (12*p - 1, 12*p + 1) and (18*p - 1, 18*p + 1) are twin primes.

%H Amiram Eldar, <a href="/A138660/b138660.txt">Table of n, a(n) for n = 1..10000</a>

%e 29 is a term since it is a prime and (12*29 - 1, 12*29 + 1) = (347, 349) and (18*29 - 1, 18*29 + 1) = (521, 523) are twin primes.

%e 1051 is a term since it is a prime and (12*1051 - 1, 12*1051+ 1) = (12611, 12613) and (18*1051 - 1, 18*1051 + 1) = (18917, 18919) are twin primes.

%t a=12;b=18;Select[Prime[Range[14^4]],PrimeQ[a*#-1]&&PrimeQ[a*#+1]&&PrimeQ[b*#-1]&&PrimeQ[b*#+1]&]

%o (Magma) [p: p in PrimesUpTo(1000)| IsPrime(12*p-1) and IsPrime(12*p+1) and IsPrime(18*p-1) and IsPrime(18*p+1)] // _Vincenzo Librandi_, Nov 24 2010

%Y Intersection of A138242 and A138248.

%Y Cf. A001097, A001359, A006512.

%K nonn

%O 1,1

%A _Vladimir Joseph Stephan Orlovsky_, May 15 2008

%E More terms from _Vincenzo Librandi_, Apr 01 2010