It is here, as explained by Alexandre Thiery. The challenge is to find a four color schema such that a 17 x 17 grid has no rectangle with the same four colors at each corner. The best known solution, shown below, has three rectangles. They are denoted by the black lines.
Who can find a schema with no such rectangles? Does one exist?
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The fact that I enjoy this so much indicates some sort of bias towards colorful things. Or maybe just pretty things, more generally.
Who can find a schema with no such rectangles? Does one exist?
####
The fact that I enjoy this so much indicates some sort of bias towards colorful things. Or maybe just pretty things, more generally.
