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%I #15 Jun 09 2018 06:29:10
%S 5,7,11,13,29,31,53,59,61,127,131,137,139,173,179,181,191,193,293,307,
%T 311,313,317,367,373,379,383,389,397,541,547,557,563,569,571,853,857,
%U 859,863,877,881,883,887,967,971,977,983,991,997,1009,1013,1019,1021
%N Primes whose integer square root is also prime.
%C The integer square root of an integer x >= 0 can be defined as floor(sqrt(x)) and the remainder of this as x - (floor(sqrt(x)))^2.
%H Robert Israel, <a href="/A135930/b135930.txt">Table of n, a(n) for n = 1..10000</a>
%H Wikipedia, <a href="http://en.wikipedia.org/wiki/Integer_square_root">Integer square root</a>
%p map(p -> select(isprime, [$p^2+1..(p+1)^2-1]), [seq(ithprime(i),i=1..10)]); # _Robert Israel_, Jun 08 2018
%t f[n_]:=PrimeQ[IntegerPart[Sqrt[n]]];lst={};Do[p=Prime[n];If[f[p],AppendTo[lst,p]],{n,6!}];lst (* _Vladimir Joseph Stephan Orlovsky_, Dec 12 2009 *)
%t Select[Prime[Range[200]],PrimeQ[IntegerPart[Sqrt[#]]]&] (* _Harvey P. Dale_, Jun 23 2016 *)
%o (PARI) { forprime(p=2, 2000, isr = sqrtint(p); if (isprime(isr), print1(p, ",") ) ) }
%Y Cf. A000196 (integer square root).
%K nonn
%O 1,1
%A _Harry J. Smith_, Dec 07 2007
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