Tag Archives: graph

17×17 4-coloring with no monochromatic rectangles

Quick, what’s special about the following picture? As just announced by Bill Gasarch, this is a grid which has been four-colored (that is, each point in the grid has been assigned one of four colors) in such a way that … Continue reading

Posted in open problems, pattern, people, pictures | Tagged , , , , , | 5 Comments

m-bracelets code

[15 January 2013: updated code to work with the latest versions of fgl and graphviz. Thanks to Conal Elliott for the updates!] By popular demand, here is the Haskell code I used to generate the images in my previous post. … Continue reading

Posted in arithmetic, computation, links, pictures, programming | Tagged , , , , | 3 Comments