On the Maximum Diameter of a Class of Distance-regular Graphs
نویسنده
چکیده
If a graph attains the bound (1.1) it is called a Moore graph if g is odd and a generalised polygon if g is even. A lot of work has been done on the classification of these graphs. Moore graphs have been studied by Hoffman and Singleton [8], Bannai and Ito [1], and Damerell [5]. Generalised polygons have been studied by Feit and Higman [7], Benson [3], and Singleton [9]. Biggs ([4]; Chapter 23) considered both types of graph as special cases of a more general family of distanceregular graphs. In this paper, we shall study this enlarged family of graphs. We shall prove that (apart from some well-known exceptions) none of them have diameter greater than 5.
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تاریخ انتشار 2006