A New Proof of the H-colouring Dichotomy
نویسنده
چکیده
In this note, we present a new proof of the H-colouring Dichotomy, which was proved by Hell and Nešetřil in 1990, and was reproved by Bulatov in 2005. The proof is much shorter than the original proof, and avoids the algebraic machinery of Bulatov’s proof.
منابع مشابه
The complexity of tropical graph homomorphisms
A tropical graph (H, c) consists of a graph H and a (not necessarily proper) vertex-colouring c of H. For a fixed tropical graph (H, c), the decision problem (H, c)-Colouring asks whether a given input tropical graph (G, c1) admits a homomorphism to (H, c), that is, a standard graph homomorphism of G to H that also preserves vertex-colours. We initiate the study of the computational complexity ...
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