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Squares such that square-+5 are primes.
2

%I #4 Nov 20 2018 18:53:49

%S 36,144,1296,5184,6084,28224,39204,41616,116964,186624,207936,242064,

%T 285156,345744,352836,443556,527076,571536,617796,646416,992016,

%U 1028196,1468944,1483524,1557504,1572516,1602756,1726596,1806336,2178576

%N Squares such that square-+5 are primes.

%t lst={};Do[p=n^2;If[PrimeQ[p-5]&&PrimeQ[p+5],AppendTo[lst,p]],{n,6,8!,6}];lst

%t Select[Range[1500]^2,AllTrue[#+{5,-5},PrimeQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* _Harvey P. Dale_, Nov 20 2018 *)

%Y Cf. A144938, A154709, A154710

%K nonn

%O 1,1

%A _Vladimir Joseph Stephan Orlovsky_, Jan 14 2009