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%I #9 Sep 28 2015 13:21:15
%S 2,10,12,28,42,60,68,108,110,122,142,180,198,200,268,282,340,378,380,
%T 418,430,488,500,502,530,612,742,788,802,838,840,912,942,948,952,1010,
%U 1080,1102,1148,1232,1270,1428,1452,1472,1502,1522,1538,1720,1778,1830
%N Numbers n such that n^2 + 13 and n^2 + 13^2 are primes.
%C Numbers are subsequence of A113536 and A176969
%C See comments and references of A176969
%H Harvey P. Dale, <a href="/A176978/b176978.txt">Table of n, a(n) for n = 1..1000</a>
%e 2^2 + 13 = 17 = prime(7), 2^2 + 13^2 = 173 = prime(40), 2 is first term.
%t Select[Range[2000],AllTrue[#^2+{13,13^2},PrimeQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* _Harvey P. Dale_, Sep 28 2015 *)
%o (PARI) isok(n) = isprime(n^2 + 13) && isprime(n^2 + 13^2); \\ _Michel Marcus_, Aug 27 2013
%Y Cf. A000040, A000290, A056899, A113536, A176371, A176969.
%K nonn
%O 1,1
%A Eva-Maria Zschorn (e-m.zschorn(AT)zaschendorf.km3.de), Apr 30 2010
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