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\noindent{\bf Doris Schattschneider }\bigskip\noindent
 Escher's Combinatorial Patterns\vskip.5cm\noindent
It is a little-known fact that M.C. Escher posed and answered some 
combinatorial questions about patterns produced in an algorithmic way.
We report on his explorations, indicate how close he came to the
 correct solutions, and pose an analagous problem in 3 dimensions.
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