Algebraic characterizations of distance-regular graphs

نویسنده

  • Miguel Angel Fiol
چکیده

We survey some old and some new characterizations of distance-regular graphs, which depend on information retrieved from their adjacency matrix. In particular, it is shown that a regular graph with d+ 1 distinct eigenvalues is distance-regular if and only if a numeric equality, involving only the spectrum of the graph and the numbers of vertices at distance d from each vertex, is satisfied.

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عنوان ژورنال:
  • Discrete Mathematics

دوره 246  شماره 

صفحات  -

تاریخ انتشار 2002