The local eigenvalues of a bipartite distance-regular graph
نویسندگان
چکیده
منابع مشابه
The local eigenvalues of a bipartite distance-regular graph
We consider a bipartite distance-regular graph Γ with vertex set X, diameter D ≥ 4, and valency k ≥ 3. For 0 ≤ i ≤ D, let Γ i (x) denote the set of vertices in X that are distance i from vertex x. We assume there exist scalars r, s, t ∈, not all zero, such that r|Γ 1 (x) ∩ Γ 1 (y) ∩ Γ 2 (z)| + s|Γ 2 (x) ∩ Γ 2 (y) ∩ Γ 1 (z)| + t = 0 let Γ 2 2 denote the graph with vertex set˜X = {y ∈ X | ∂(x, y)...
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Article history: Received 9 April 2013 Accepted 15 December 2013 Available online 13 January 2014 Submitted by R. Brualdi
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ژورنال
عنوان ژورنال: European Journal of Combinatorics
سال: 2015
ISSN: 0195-6698
DOI: 10.1016/j.ejc.2014.10.011