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|A plane topological disk (i.e. a plane region without "holes") consisting of n edge-to-edge adjacent squares is called a polyomino. This site offers a shape description: in every border square cell of a polyomino we could introduce two-sided mirrors perpendicular to the internal edges in their mid-points. After a series of reflections, a ray of light will "describe" the shape: a closed Dragon curve. If we denote a reflection in a border mirror by 0, and a reflection in an internal mirror by 1, we have 0-1 words (or symbols) for polyominoes, where these words are cyclically equivalent (can be read starting from any sign 0 or 1 and ending in it). Illustrations; conclusions about symmetry; polyomino growing; curvilinear shapes; and Lunda polyominoes.|
|Levels:||Middle School (6-8), High School (9-12)|
|Resource Types:||Graphics, Problems/Puzzles|
|Math Topics:||Euclidean Plane Geometry, Symmetry/Tessellations|
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