Distinguishing graphs by the number of homomorphisms
نویسنده
چکیده
A homomorphism from one graph to another is a map that sends vertices to vertices and edges to edges. We denote the number of homomorphisms from G to H by |G → H|. If F is a collection of graphs, we say that F distinguishes graphs G and H if there is some member X of F such that |G → X| 6= |H → X|. F is a distinguishing family if it distinguishes all pairs of graphs. We show that various collections of graphs are a distinguishing family.
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عنوان ژورنال:
- Discussiones Mathematicae Graph Theory
دوره 15 شماره
صفحات -
تاریخ انتشار 1995