A Characterization of Half-Dual Polar Graphs
نویسندگان
چکیده
منابع مشابه
A Characterization of Half-Dual Polar Graphs
By a graph 0, we shall mean a finite, simple and undirected graph. For x in V (0), the vertex set of 0, let 0i (x) be the set of vertices of 0 at a distance i from x . A distance-regular graph of diameter d is one for which the parameters ci = |0i−1(x) ∩ 01(y)|, ai = |0i (x) ∩ 01(y)| and bi = |0i+1(x) ∩ 01(y)| depend only on the distance i between x and y. It is clear that ai = b0 − bi − ci . T...
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ژورنال
عنوان ژورنال: European Journal of Combinatorics
سال: 1999
ISSN: 0195-6698
DOI: 10.1006/eujc.1998.0270