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List giving pairs of primes of the form 10k+3 and 10k+13.
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%I #9 Sep 08 2022 08:45:07

%S 3,13,13,23,43,53,73,83,103,113,163,173,223,233,283,293,373,383,433,

%T 443,643,653,673,683,733,743,853,863,1093,1103,1153,1163,1213,1223,

%U 1423,1433,1483,1493,1543,1553,1723,1733,1993,2003,2053,2063,2143,2153

%N List giving pairs of primes of the form 10k+3 and 10k+13.

%C Except for 3,13, each pair is 30k+13 and 30k+23.

%H Vincenzo Librandi, <a href="/A076747/b076747.txt">Table of n, a(n) for n = 1..1000</a>

%e 163 and 173 are in the sequence because both are prime; 193 and 203 aren't because not both are primes.

%t Flatten[Select[Table[10 n + {3, 13}, {n, 0, 300}], And@@PrimeQ[#] &]] (* _Vincenzo Librandi_, Jun 08 2016 *)

%o (PARI) forstep(x=3,2200,10, if(isprime(x) && isprime(x+10), print1(x" "x+10" ")))

%o (Magma) &cat[[10*k+3, 10*k+13]: k in [0..250]| IsPrime(10*k+3) and IsPrime(10*k+13)]; // _Vincenzo Librandi_, Jun 08 2016

%Y Cf. A076746.

%K nonn

%O 1,1

%A _Cino Hilliard_, Nov 12 2002

%E Edited by _Don Reble_, Jun 08 2003