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%I #29 Sep 08 2022 08:44:49
%S 1,4,13,16,19,25,28,43,49,55,76,79,88,106,118,121,139,145,151,154,175,
%T 190,205,208,211,235,238,253,259,268,271,301,310,370,373,376,391,400,
%U 403,415,433,445,484,490,508,511,523,544,568,580,583,589,610
%N Numbers k such that k^2 + k + 9 is prime.
%H Vincenzo Librandi, <a href="/A027757/b027757.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>
%t Select[Range[2500], PrimeQ[#^2 + # + 9] &] (* _Harvey P. Dale_, Dec 01 2010 *)
%o (Magma) [n: n in [0..1000] |IsPrime(n^2+n+9)] // _Vincenzo Librandi_, Nov 20 2010
%o (PARI) is(n)=isprime(n^2+n+9) \\ _Charles R Greathouse IV_, Feb 20 2017
%K nonn
%O 1,2
%A _Patrick De Geest_
%E Additional terms from _Harvey P. Dale_, Dec 01 2010
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