Fractional Multiples of Graphs and the Density of Vertex-Transitive Graphs
نویسنده
چکیده
We introduce a construction called the fractional multiples of a graph. These graphs are used to settle a question raised by E. Welzl: We show that if G and H are vertex-transitive graphs such that there exists a homomorphism fromG toH but no homomorphism fromH to G, then there exists a vertex-transitive graph that is homomorphically “in between” G and H.
منابع مشابه
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