1 October 2025
For the #Mathober 2025 day 1 prompt ‘Link’, I offer the following image. It is based on a geometrical mosaic of intertwining loops from the Hall of the Two Sisters in the Alhambra, but has been redrawn to be mathematically exact.
Here are some relevant resources:
The LaTeX/TikZ source code (Licensed under the LaTeX Project Public Licence v1.3c).
The image in PDF format. (Licensed under the Creative Commons Attribution–ShareAlike 4.0 International Licence)
Another PDF showing ‘grid coordinates’ for the mosaic. (Licensed under the Creative Commons Attribution–ShareAlike 4.0 International Licence)
An illustration of the mosaic from J. Goury, O. Jones & P. de Gayangos, Plans, Elevations, Sections, and Details of the Alhambra. (London: Owen Jones, 1842–5). The book is available on the Internet Archive: volume 1, volume 2.
Although it is not required by the licences, if you use this work, a link to my book Form & Number: A History of Mathematical Beauty (for which this image was originally drawn) would be appreciated: https://archive.org/details/cain_formandnumber_ebook_large