Information and instructions


Competition in symmetry recognition will end on August 31th, 2013 at 11.00 central European time.

To apply for the competition you must fill the form that consists of password of 8 alphanumeric characters of your choice (required) which is to be used for consequent trials; name, surname and country (optional). Of course you may use pseudonym, but in case a medal is entitled the data from the form will be used. After filling the form press »start«.


There are three disciplines: Recognition of Leonardo’s group, recognition of frieze group and recognition of wallpaper group (plane crystalographics group)

The task is to find the group of each of 20 randomly chosen figures in less than 5 minutes. The penalty for wrong answer is 20 seconds. Your answer must be correct to continue. Pressing »start again« stops the current trial and begins new one with no need to fill the form. Extra points are awarded if you finish before 5 minutes.

Figures are generated by Mathematica notebook Plane Tiling by Xah Lee extended to cover Leonardo’s and frieze groups. Here are some links that cover the content.

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Xah Lee
A. Kozomara