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%I #23 Sep 08 2022 08:44:49
%S 0,1,2,3,6,7,11,16,17,18,21,23,27,31,32,38,42,48,51,62,67,72,73,76,77,
%T 83,86,91,93,97,108,111,116,121,126,133,136,137,146,153,158,163,172,
%U 177,182,188,191,192,193,202,212,213,216,223,226,231,247,248
%N Numbers k such that k^2 + k + 5 is prime.
%H Seiichi Manyama, <a href="/A027754/b027754.txt">Table of n, a(n) for n = 1..10000</a>
%H Patrick De Geest, <a href="http://www.worldofnumbers.com/index.html">World!Of Numbers</a>
%e Since 3^2 + 3 + 5 = 17, which is prime, 3 is in the sequence.
%e Since 4^2 + 4 + 5 = 25 = 5^2, 4 is not in the sequence.
%t Select[Range[0, 499], PrimeQ[#^2 + # + 5] &] (* _Alonso del Arte_, Nov 28 2016 *)
%o (Magma) [n: n in [0..1000] |IsPrime(n^2+n+5)] // _Vincenzo Librandi_, Nov 20 2010
%Y Cf. A014556, A027755.
%K nonn
%O 1,3
%A _Patrick De Geest_
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