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Primes p such that p+(floor(Sqrt(p)))^2 is prime.
1

%I #4 Apr 24 2013 09:07:33

%S 2,7,37,43,47,67,73,149,163,167,223,337,349,353,359,409,421,439,487,

%T 499,577,587,617,691,787,823,829,911,947,1039,1063,1087,1201,1297,

%U 1321,1361,1367,1453,1459,1483,1609,1621,1657,1777,1783,1987,1993,2011,2137,2143

%N Primes p such that p+(floor(Sqrt(p)))^2 is prime.

%C 2+1=3 prime, 7+4=11 prime, 37+36=73 prime,...

%t f[n_]:=n+(Floor[Sqrt[n]])^2;lst={};Do[p=Prime[n];If[PrimeQ[f[p]],AppendTo[lst,p]],{n,7!}];lst

%t Select[Prime[Range[400]],PrimeQ[#+Floor[Sqrt[#]]^2]&] (* _Harvey P. Dale_, Apr 24 2013 *)

%Y Cf. A086085, A086086, A135932, A173826

%K nonn

%O 1,1

%A _Vladimir Joseph Stephan Orlovsky_, Feb 25 2010