A036701 - OEIS

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A036701

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

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, 21, 21, 22, 24, 23, 26, 25, 27, 29, 25, 30, 28, 33, 31, 30, 33, 33, 36, 36, 33, 37, 37, 39, 40, 41, 41, 39, 42, 42, 46, 43, 46, 45, 47

(list; graph; refs; listen; history; text; internal format)

OFFSET

0,4

LINKS

Robert Israel, Table of n, a(n) for n = 0..2000

Index entries for Gaussian integers and primes

MAPLE

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

for a from 1 to N do

for b from 0 to a-1 do

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

if r > N then break fi;