A036701 - OEIS

%I #12 Dec 18 2018 12:06:18

%S 0,1,1,2,3,4,4,5,6,7,8,8,8,11,11,12,11,13,14,15,16,15,18,17,18,21,20,

%T 21,21,22,24,23,26,25,27,29,25,30,28,33,31,30,33,33,36,36,33,37,37,39,

%U 40,41,41,39,42,42,46,43,46,45,47

%N a(n)=number of Gaussian integers z=a+bi satisfying n-1<|z|<=n, a>=0, 0<=b<a.

%H Robert Israel, <a href="/A036701/b036701.txt">Table of n, a(n) for n = 0..2000</a>

%H <a href="/index/Ga#gaussians">Index entries for Gaussian integers and primes</a>

%p N:= 100: A:= Array(0..N):

%p for a from 1 to N do

%p   for b from 0 to a-1 do

%p      r:= ceil(sqrt(a^2+b^2));

%p      if r > N then break fi;

%p      A[r]:= A[r]+1;

%p od od:

%p seq(A[i],i=0..N); # _Robert Israel_, Dec 18 2018

%Y Cf. A036700.

%K nonn

%O 0,4

%A _Clark Kimberling_