On the algorithmic aspects of Hedetniemi’s conjecture
نویسنده
چکیده
We present a polynomial algorithm, implicit in the work of ElZahar and Sauer, which inputs a 3-colouring of a categorical product of two graphs and outputs a 3-colouring of one of the factors. We raise a question about the existence of polynomial algorithms for colouring the vertices of some graphs in terms of intrinsic succint description of the vertices rather than in terms of the (exponential) size of the graph. Dedicated to Jaroslav Nešetřil on the occasion of his 60th birthday
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