magic circles
MagicCircles
2004-03-13 19:50:33
2004-11-19 17:14:55
Definition
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Given $n$ circles which intersect $k$ times, the set of circles is referred to as \emph{magic circles} if there exists a numbering (using $\{1,\ldots,k\}$) of the intersections of the $n$ circles such that the sum of the numbers at the intersections along each circle is the same constant for all circles.
Further reference:
http://www.cgl.uwaterloo.ca/~smann/Magic/