OFFSET
1,1
LINKS
Robert Israel, Table of n, a(n) for n = 1..10000
Eric Weisstein's World of Mathematics, Gauss's Circle Problem
MAPLE
N:= 100: # to get a(1) to a(N)
B:= Array(1..N);
for i from 0 to N do
for j from i while i^2 + j^2 <= N^2 do
v:= ceil(sqrt(i^2+j^2));
if [i, j] = [0, 0] then m:= 1; v:= 1
elif i=0 or i=j then m:= 4
else m:= 8
fi;
B[v]:= B[v]+m;
od
od:
A000328:= ListTools:-PartialSums(convert(B, list)):
seq(numer(A000328[n]/n^2), n=1..N); # Robert Israel, May 28 2015
CROSSREFS
KEYWORD
nonn,frac
AUTHOR
Eric W. Weisstein, Apr 17 2004
EXTENSIONS
Definition edited by Robert Israel, May 28 2015
STATUS
approved