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Seven Coins Puzzle

Draw an {N/D} star polygon - a polygon whose N vertices are uniformly distributed on a circle, but are connected by counting the D-th neighbor. Regular polygons correspond to D = 1, and their symbol is usually abbreviated to {N}.

In the applet the symbol {N/D} appears in the lower right corner. Both numbers can be modified by clicking a little off their center lines. When N and D have a common factor, there are conflicting view points as to whether the configuration of nodes and edges represents a single polygon or a collection of polygons with fewer vertices. However, for the puzzle we shall assume that N and D are mutually prime. In the classical case, N = 8 and D = 3. The object is to place 7 coins (N - 1 in general) at the vertices of the star. A coin may only be placed by dragging the cursor along an edge from one vertex to another.

<hr> <h3> This applet requires Sun's Java VM 2 which your browser may perceive as a popup. Which it is not. If you want to see the applet work, visit Sun's website at http://www.java.com/en/download/index.jsp, download and install Java VM and enjoy the applet. </h3> <hr>

Explanation

Copyright © 1996-2008 Alexander Bogomolny



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