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A138660 Primes p such that (12*p - 1, 12*p + 1) and (18*p - 1, 18*p + 1) are twin primes.

%I A138660 #23 Jan 15 2025 10:59:26
%S A138660 29,1051,6719,9059,10501,27749,27791,36749,51421,83761,86729,108751,
%T A138660 115249,120049,124139,124529,138629,148861,152839,162091,169009,
%U A138660 176609,178249,178921,202481,203141,209621,228199,232681,244411,302779,309259
%N A138660 Primes p such that (12*p - 1, 12*p + 1) and (18*p - 1, 18*p + 1) are twin primes.
%H A138660 Amiram Eldar, <a href="/A138660/b138660.txt">Table of n, a(n) for n = 1..10000</a>
%e A138660 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 A138660 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 A138660 a=12;b=18;Select[Prime[Range[14^4]],PrimeQ[a*#-1]&&PrimeQ[a*#+1]&&PrimeQ[b*#-1]&&PrimeQ[b*#+1]&]
%t A138660 Select[Prime[Range[30000]],AllTrue[{12#-1,12#+1,18#-1,18#+1},PrimeQ]&] (* _Harvey P. Dale_, Dec 31 2024 *)
%o A138660 (Magma) [p: p in PrimesUpTo(100000)| 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 A138660 Intersection of A138242 and A138248.
%Y A138660 Cf. A001097, A001359, A006512.
%K A138660 nonn
%O A138660 1,1
%A A138660 _Vladimir Joseph Stephan Orlovsky_, May 15 2008
%E A138660 More terms from _Vincenzo Librandi_, Apr 01 2010