The Friendship Problem on Graphs
نویسندگان
چکیده
In this paper we provide a purely combinatorial proof of the Friendship Theorem, which has been first proven by P. Erdös et al. by using also algebraic methods. Moreover, we generalize this theorem in a natural way, assuming that every pair of nodes occupies ≥ 2 common neighbors. We prove that every graph, which satisfies this generalized -friendship condition, is a regular graph.
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ورودعنوان ژورنال:
- Multiple-Valued Logic and Soft Computing
دوره 27 شماره
صفحات -
تاریخ انتشار 2016