Sand drawings and Gaussian graphs

Sand drawings form a part of many cultural traditions. Depending on the part of the world in which they occur, such drawings have different names such as sona, kolam, and nitus drawings. In this paper, we show connections between a special class of sand drawings and mathematical objects studied in the disciplines of graph theory and topology called Gaussian graphs. Motivated by this connection, we further our study to include analysis of some properties of sand drawings. In particular, we study the number of different drawings, show how to generate them, and show connections to the well-known Traveling Salesman Problem in computer science. §A preliminary version of this paper appeared at BRIDGES 2006 1.

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