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%I #12 Dec 11 2020 06:41:46
%S 9,81,225,441,1089,13689,56169,74529,91809,95481,149769,184041,194481,
%T 199809,263169,314721,328329,370881,651249,804609,1071225,1147041,
%U 1238769,1306449,1520289,1535121,1718721,2442969,2595321,2614689
%N Squares k such that k - 2 and k + 2 are prime.
%H Charles R Greathouse IV, <a href="/A144938/b144938.txt">Table of n, a(n) for n = 1..10000</a>
%F A087679 intersect A000290. - _R. J. Mathar_, Dec 11 2020
%t lst={};Do[p=n^2;If[PrimeQ[p-2]&&PrimeQ[p+2],AppendTo[lst,p]],{n,1,7!,2}];lst
%o (PARI) forstep(n=3,1e3,6,if(isprime(n^2-2)&&isprime(n^2+2),print1(n^2", "))) \\ _Charles R Greathouse IV_, Oct 05 2011
%Y Cf. A000290, A087679.
%K nonn,easy
%O 1,1
%A _Vladimir Joseph Stephan Orlovsky_, Sep 25 2008