On graphs isomorphic to their neighbour and non-neighbour sets
نویسنده
چکیده
The paper contains a construction of a universal countable graph, different from the Rado graph, such that for any of its vertices both the neighbourhood and the non-neighbourhood induce subgraphs isomorphic to the whole graph. This solves an open problem proposed by A. Bonato; see Problem 20 in [5]. We supply a construction of several non-isomorphic graphs with the property, and consider tournaments with an analogous property.
منابع مشابه
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ورودعنوان ژورنال:
- Eur. J. Comb.
دوره 31 شماره
صفحات -
تاریخ انتشار 2010