2× n Grids have Unbounded Anagram-Free Chromatic Number

05/05/2021
by   Saman Bazarghani, et al.
0

We show that anagram-free vertex colouring a 2× n square grid requires a number of colours that increases with n. This answers an open question in Wilson's thesis and shows that even graphs of pathwidth 2 do not have anagram-free colourings with a bounded number of colours.

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