Seems to be nothing more than an ad for a book? Also, these things are usually called “Space-filling curves” (<a href="https://en.wikipedia.org/wiki/Space-filling_curve" rel="nofollow">https://en.wikipedia.org/wiki/Space-filling_curve</a>).<p>EDIT: I missed the “Read Online” link - it is indeed a whole book about space-filling curves with lots of pictures.
uses an image I made & uploaded to wikipedia without credit :(
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<a href="http://en.wikipedia.org/wiki/Iterated_function_system#mediaviewer/File:Ifs-construction.png" rel="nofollow">http://en.wikipedia.org/wiki/Iterated_function_system#mediav...</a>
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