This tile was found by Casey Mann in 2002.
(The png drawing was made by the author.)
Two copies of the tile can surround a third copy completly.
The tile does not admit a tiling of the plane.
Reference:
Casey Mann, (2002). A tile with surround number 2. The American Mathematical Monthly,
Vol. 109, No. 4, pp. 383-388.
With a modified Voderberg tile it is possible to enlarge the small hooks and catches.
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Walter Trump, Nürnberg, Germany, ms(at)trump.de, © 2025-02-06 (last modified: 2025-02-16)