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%I #28 Sep 08 2022 08:44:47
%S 2,3,5,23,29,47,53,59,89,107,113,137,179,197,227,233,257,263,293,317,
%T 359,389,419,509,557,587,593,599,617,653,659,683,839,857,863,887,947,
%U 977,1013,1097,1103,1163,1193,1217,1223,1229,1259,1277,1283,1307,1319,1409
%N Primes p such that 8*p + 7 is also prime.
%H Vincenzo Librandi, <a href="/A023231/b023231.txt">Table of n, a(n) for n = 1..1000</a>
%e For p = 3, 8*p + 7 = 31;
%e for p = 179, 8*p + 7 = 1439.
%p a := proc (n) if isprime(n) = true and isprime(8*n+7) = true then n else end if end proc: seq(a(n), n = 1 .. 1500); # _Emeric Deutsch_, Dec 30 2008
%t Select[Prime@Range@500, PrimeQ[8 # + 7] &] (* _Vincenzo Librandi_, May 19 2014 *)
%o (Magma) [n: n in PrimesUpTo(1500) | IsPrime(8*n+7)]; // _Vincenzo Librandi_, Nov 20 2010
%Y Cf. A139487, A007522.
%K nonn,easy
%O 1,1
%A _David W. Wilson_
%E Edited by _N. J. A. Sloane_, Mar 11 2009 at the suggestion of _R. J. Mathar_
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