%I
%S 1,4,9,12,21,32,37,52,65,80,97,112,137,152,177,208,225,256,289,316,
%T 349,384,421,448,489,536,577,612,665,716,749,812,857,912,965,1020,
%U 1085,1124,1201,1264,1313
%N Number of unit squares at least 50% covered by a circle inscribed in an integer square of size n X n.
%C From _Robert G. Wilson v_, Mar 20 2017: (Start)
%C For n odd, the center of the circle is in the middle of the center square and thus a(2n1) == 1 (mod 4).
%C For n even, the center of the circle is at the four corners of the center 4 squares and thus a(2n) == 0 (mod 4). (End)
%e a(2)=4 because an inscribed circle in a 2 X 2 grid covers 50% of all the unit squares within it.
%K nonn,more
%O 1,2
%A Joe K. Crump (joecr(AT)carolina.rr.com)
