Distance-Regular Graphs with ci = bd−i and Antipodal Double Covers
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چکیده
Throughout this paper, we assume Γ is a connected finite undirected graph without loops or multiple edges. We identify Γ with the set of vertices. For vertices u and x in Γ, let ∂(u, x) denote the distance between u and x in Γ, i.e., the length of a shortest path connecting u and x. Let d = d(Γ) denote the diameter of Γ, i.e., the maximal distance between any two vertices in Γ. Let Γi(u) = { y ∈ Γ | ∂(u, y) = i }.
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تاریخ انتشار 1998