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%I #22 Feb 28 2023 08:59:18
%S 2,8,10,20,32,38,40,52,58,62,70,82,88,98,100,110,112,118,140,142,160,
%T 170,188,190,200,202,212,218,220,242,298,308,320,332,350,358,368,380,
%U 382,400,410,412,422,448,472,482,490,502,512,530,538,542,568,572,578
%N Numbers k such that k^2 + 9 is prime.
%H G. C. Greubel, <a href="/A114272/b114272.txt">Table of n, a(n) for n = 1..1000</a>
%F a(n) = 2 * A002970(n). - _Michel Marcus_, Jan 20 2015
%t lst={};Do[If[PrimeQ[n^2+9], AppendTo[lst, n]], {n, 600}];lst (* _Vladimir Joseph Stephan Orlovsky_, Aug 26 2008 *)
%t Select[Range[2,600,2],PrimeQ[#^2+9]&] (* _Harvey P. Dale_, Feb 28 2023 *)
%o (PARI) is(n)=isprime(n^2+9) \\ _Charles R Greathouse IV_, Feb 17 2017
%Y Other sequences of the type "Numbers k such that k^2 + i is prime": A005574 (i=1), A067201 (i=2), A049422 (i=3), A007591 (i=4), A078402 (i=5), A114269 (i=6), A114270 (i=7), A114271 (i=8), this sequence (i=9), A114273 (i=10), A114274 (i=11), A114275 (i=12).
%K nonn
%O 1,1
%A _Zak Seidov_, Nov 19 2005
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