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Number of hexagons (side length 1) that intersect the circumference of a circle of radius n centered at a lattice point.
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%I #6 Jun 26 2014 18:47:35

%S 3,9,12,15,21,24,27,39,42,39,51,54,51,63,66,69,81,78,75,99,96,93,105,

%T 114,105,123,120,117,141,138,129,147,156,153,159,162,159,177,180,171,

%U 201,192,183,201,204,201,219,216,207,237,240,225,249,258,243,267,246,261,285,276

%N Number of hexagons (side length 1) that intersect the circumference of a circle of radius n centered at a lattice point.

%C The pattern repeats itself at every 2*Pi/3 sector along the circumference. The hexagon count per one-third sector by rows can be arranged as an irregular triangle. The double hexagons in a row are symmetrically placed. See illustration.

%H Kival Ngaokrajang, <a href="/A244147/a244147.pdf">Illustration of initial terms</a>

%H Kival Ngaokrajang, <a href="/A244147/a244147.txt">Small Basic program</a>

%o (Small Basic) See links.

%Y Cf. A242118, A242394, A242395.

%K nonn

%O 1,1

%A _Kival Ngaokrajang_, Jun 21 2014