%I #35 Sep 08 2022 08:44:47
%S 2,5,7,13,17,19,23,37,41,43,47,59,61,71,73,83,101,103,127,131,139,149,
%T 157,197,199,223,233,239,257,269,271,281,293,307,311,331,349,353,373,
%U 401,409,421,433,463,467,479,491,499,503,509,541,547,563,577,587,593,607,619
%N Primes p such that 10*p + 9 is also prime.
%H John Cerkan, <a href="/A023240/b023240.txt">Table of n, a(n) for n = 1..10000</a>
%t Select[Prime@ Range@ 120, PrimeQ[10 # + 9] &] (* _Michael De Vlieger_, Sep 12 2016 *)
%o (Magma) [ n: n in PrimesUpTo(700) | IsPrime(10*n+9) ]; // _Vincenzo Librandi_, Nov 20 2010
%Y Subsequence of A102700.
%K nonn
%O 1,1
%A _David W. Wilson_
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