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A155932 Integers a(n) such that cube(n)-square(x) and cube(n)+square(x) are primes. 0

%I

%S 3,6,7,8,10,13,15,18,20,21,22,28,33,35,37,39,42,43,45,48,52,57,58,60,

%T 62,63,68,72,73,75,77,78,80,82,83,85,86,87,90,91,92,93,95,97,99,102,

%U 103,105,106,107,108,111,112,113,115,117,120,123,125,128,129,132,133,135

%N Integers a(n) such that cube(n)-square(x) and cube(n)+square(x) are primes.

%C 3^3-2^2=23;3^3+2^2=31, 6^3-5^2=191;6^3+5^2=241, 7^3-6^2=307;7^3+6^2=379, ...

%t lst={};Do[k=n;c=n^3;Label[ax];s=k^2;p1=c-s;p2=c+s;If[PrimeQ[p1]&&PrimeQ[p2],AppendTo[lst,n],k--;If[k>0,Goto[ax]]],{n,2*5!}];lst

%Y Cf. A155929, A155930, A155931

%K nonn

%O 1,1

%A _Vladimir Joseph Stephan Orlovsky_, Jan 30 2009

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Last modified September 18 07:58 EDT 2019. Contains 327168 sequences. (Running on oeis4.)