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A333462 a(n) is the number of Gaussian integers z such that (n-1)/2 < |z| <= n/2, divided by 4.

%I A333462 #16 Mar 27 2020 13:49:21
%S A333462 0,1,1,1,2,2,2,3,5,3,4,4,6,3,7,5,7,7,10,6,8,7,11,5,12,10,12,9,13,11,
%T A333462 10,12,16,10,18,9,19,11,18,14,14,15,21,15,20,14,22,13,23,19,23,17,24,
%U A333462 18,22,19,27,17,26,22,28,17,31,21,26,24,28,26,30,27,29,21
%N A333462 a(n) is the number of Gaussian integers z such that (n-1)/2 < |z| <= n/2, divided by 4.
%H A333462 Hugo Pfoertner, <a href="/A333462/b333462.txt">Table of n, a(n) for n = 1..10000</a>
%o A333462 (PARI) c=vectorsmall(2000000);for(x=1,1000,my(x2=x*x);c[x2]++;c[x2+x2]++;for(y=1,x-1,my(y2=y*y);c[x2+y2]+=2));
%o A333462 a(n)=sum(k=ceil((1+(n-1)^2)/4),floor(n^2/4),c[k]);
%o A333462 for(k=1,72,print1(a(k),", "))
%Y A333462 Cf. A004018, A232705, A333572, A333573.
%K A333462 nonn
%O A333462 1,5
%A A333462 _Hugo Pfoertner_, Mar 26 2020