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%I #14 Sep 08 2022 08:45:35
%S 0,2,3,4,7,9,10,11,13,14,17,18,20,21,23,24,25,27,28,30,31,34,37,41,42,
%T 44,48,49,51,53,56,59,60,63,65,66,67,69,70,73,74,77,79,80,81,83,88,90,
%U 91,93,94,95,100,101,104,107,111,114,115,116,119,122,125,129,135,137
%N Numbers n such that n^2 + n + 257 is prime.
%H Harvey P. Dale, <a href="/A141489/b141489.txt">Table of n, a(n) for n = 1..1000</a>
%e If n=0, then n^2 + n + 257 = 257 (prime).
%e If n=100, then n^2 + n + 257 = 10357 (prime).
%t Select[Range[0,200],PrimeQ[#^2+#+257]&] (* _Harvey P. Dale_, Jun 07 2016 *)
%o (Magma) [n: n in [0..5000] |IsPrime(n^2+n+257)] // _Vincenzo Librandi_, Nov 25 2010
%o (PARI) isok(n) = isprime(n^2+n+257); \\ _Michel Marcus_, Mar 12 2017
%Y Cf. A002837, A056561, A133157, A133160.
%K nonn
%O 1,2
%A _Parthasarathy Nambi_, Aug 09 2008
%E More terms from _Vincenzo Librandi_, Mar 25 2010