A tiling consisting of a rhombus such that 17 rhombuses fit around a point and a second tile in the shape of six rhombuses stuck together. These two tiles can fill the plane in exactly four different ways. Two tiles which tile the plane in ways can be constructed using a rhombus of a shape such that pack around a point together with a complex piece made by sticking rhombuses together (Wells 1991).
Harborth's Tiling
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References
Harborth, H. "Prescribed Numbers of Tiles and Tilings." Math. Gaz. 61, 296-299, 1977.Wells, D. The Penguin Dictionary of Curious and Interesting Geometry. Middlesex, England: Penguin Books, pp. 90-91, 1991.Referenced on Wolfram|Alpha
Harborth's TilingCite this as:
Weisstein, Eric W. "Harborth's Tiling." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/HarborthsTiling.html