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%I #9 Sep 08 2022 08:45:51
%S 2,5,7,17,19,23,29,47,73,83,89,97,107,113,127,137,149,163,197,227,229,
%T 233,239,257,269,307,359,367,373,379,439,449,557,569,619,647,673,727,
%U 739,769,797,827,877,883,919,977,983,997,1009,1033,1039,1087,1117,1123
%N Primes p such that 20*p^2+32*p+13 is also prime.
%H Vincenzo Librandi, <a href="/A174281/b174281.txt">Table of n, a(n) for n = 1..1000</a>
%e For p=2, 20*2^2+32*2+13=157; p=5, 20*5^2+32*5+13=673.
%t Select[Prime[Range[200]], PrimeQ[20 #^2 + 32 # + 13]&] (* _Vincenzo Librandi_, Apr 16 2013 *)
%o (Magma) [p: p in PrimesUpTo(2000)| IsPrime(20*p^2+32*p+13)];
%Y Cf. A154414.
%K nonn,easy
%O 1,1
%A _Vincenzo Librandi_, Mar 15 2010
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