An Eigenvalue Characterization of Antipodal Distance Regular Graphs
نویسنده
چکیده
Let Γ be a regular (connected) graph with n vertices and d + 1 distinct eigenvalues. As a main result, it is shown that Γ is an r-antipodal distanceregular graph if and only if the distance graph Γd is constituted by disjoint copies of the complete graph Kr, with r satisfying an expression in terms of n and the distinct eigenvalues. AMS subject classifications. 05C50 05E30
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عنوان ژورنال:
- Electr. J. Comb.
دوره 4 شماره
صفحات -
تاریخ انتشار 1997