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%I #23 Dec 18 2016 10:47:08
%S 3,113,907,3019,3631,5281,6361,7853,8171,11689,14957,16741,17203,
%T 20611,33329,36643,38707,63347,68813,96211,115811,126923,128189,
%U 129461,169093,172021,234139,241051,248063,301907,319691,340049,367453,380459,382649,387047,448883
%N Primes of the form: floor(Pi*n^2).
%H K. D. Bajpai, <a href="/A227794/b227794.txt">Table of n, a(n) for n = 1..1500</a>
%e a(2)=113: Pi*6^2 = 113.09 and 113 is prime.
%e a(3)=907: Pi*17^2 = 907.92 and 907 is prime.
%p KD:= proc() local a; a:=floor(evalf( Pi*n^2)); if isprime(a) then RETURN(a): fi; end: seq(KD(),n=1..1000);
%t Select[Floor[Pi*Range[400]^2],PrimeQ] (* _Harvey P. Dale_, Dec 18 2016 *)
%o (PARI) is(n)=my(r=sqrtint((n+1)\Pi)); Pi*r^2>n && isprime(n) \\ _Charles R Greathouse IV_, Sep 23 2013
%Y Cf. A066643 (floor(Pi*n^2)), A067559 (n that produce primes).
%K nonn
%O 1,1
%A _K. D. Bajpai_, Sep 23 2013
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