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Primes p such that 36*p-1 and 36*p+1 are twin primes.
1

%I #5 Jan 14 2019 14:29:29

%S 2,3,5,23,107,137,157,163,193,233,457,577,647,677,857,1013,1123,1223,

%T 1237,1783,1867,1873,2243,2417,2467,2683,2957,3407,3413,3517,3797,

%U 4373,4447,4603,4903,5413,5437,5813,6053,6073,6323,6577,6823,6863,7207,7793

%N Primes p such that 36*p-1 and 36*p+1 are twin primes.

%H Robert Israel, <a href="/A138655/b138655.txt">Table of n, a(n) for n = 1..10000</a>

%e 36*2-1=71, 36*2+1=73; 36*3-1=107, 36*p+1=109;...

%p Res:= NULL: count:= 0:

%p p:= 1:

%p while count < 100 do

%p p:= nextprime(p);

%p if isprime(36*p-1) and isprime(36*p+1) then

%p count:= count+1; Res:= Res, p;

%p fi

%p od:

%p Res; # _Robert Israel_, Jan 14 2019

%t a=36;Select[Prime[Range[10^3]],PrimeQ[a*#-1]&&PrimeQ[a*#+1]&]

%K nonn

%O 1,1

%A _Vladimir Joseph Stephan Orlovsky_, May 15 2008