Two results concerning distance-regular directed graphs
نویسندگان
چکیده
The study of distance-regular directed graphs can be reduced to that of short distance-regular directed graphs. We consider the eigenspaces of the intersection matrix of a short distance-regular directed graph and show that nearly all the eigenvalues are nonreal. Next we show that a nontrivial short distance-regular directed graph is primitive.
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ورودعنوان ژورنال:
- Australasian J. Combinatorics
دوره 23 شماره
صفحات -
تاریخ انتشار 2001