Homomorphisms and amalgamation
نویسنده
چکیده
We prove that for each ,nite core graph G, the class of all graphs admitting a homomorphism into G is a pseudo-amalgamation class, in the sense of Fra01ss2 e. This fact gives rise to a countably in,nite universal pseudo-homogeneous graph which shares some of the properties of the in,nite random graph. Our methods apply simultaneously to G-colourings in several classes of relational structures, such as the classes of directed graphs or hypergraphs. c © 2003 Elsevier B.V. All rights reserved.
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ورودعنوان ژورنال:
- Discrete Mathematics
دوره 270 شماره
صفحات -
تاریخ انتشار 2003