The Q-polynomial idempotents of a distance-regular graph
نویسندگان
چکیده
منابع مشابه
On bipartite Q-polynomial distance-regular graphs
Let Γ denote a bipartite Q-polynomial distance-regular graph with vertex set X, diameter d ≥ 3 and valency k ≥ 3. Let RX denote the vector space over R consisting of column vectors with entries in R and rows indexed by X. For z ∈ X, let ẑ denote the vector in RX with a 1 in the z-coordinate, and 0 in all other coordinates. Fix x, y ∈ X such that ∂(x, y) = 2, where ∂ denotes path-length distance...
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We consider a Q-polynomial distance-regular graph Γ with vertex set X and diameter D ≥ 3. For μ, ν ∈ {↓, ↑} we define a direct sum decomposition of the standard module V = CX, called the (μ, ν)–split decomposition. For this decomposition we compute the complex conjugate and transpose of the associated primitive idempotents. Now fix b, β ∈ C such that b 6= 1 and assume Γ has classical parameters...
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ژورنال
عنوان ژورنال: Journal of Combinatorial Theory, Series B
سال: 2010
ISSN: 0095-8956
DOI: 10.1016/j.jctb.2010.07.002