Tight Distance-regular Graphs and the Subconstituent Algebra
نویسندگان
چکیده
منابع مشابه
Taut distance-regular graphs and the subconstituent algebra
We consider a bipartite distance-regular graph Γ with diameter D ≥ 4 and valency k ≥ 3. Let X denote the vertex set of Γ and fix x ∈ X. Let Γ22 denote the graph with vertex set X̆ = {y ∈ X | ∂(x, y) = 2}, and edge set R̆ = {yz | y, z ∈ X̆, ∂(y, z) = 2}, where ∂ is the path-length distance function for Γ. The graph Γ22 has exactly k2 vertices, where k2 is the second valency of Γ. Let η1, η2, . . . ...
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ژورنال
عنوان ژورنال: European Journal of Combinatorics
سال: 2002
ISSN: 0195-6698
DOI: 10.1006/eujc.2002.0597