New parameters of subsets in polynomial association schemes
نویسندگان
چکیده
منابع مشابه
Width and dual width of subsets in polynomial association schemes
The width of a subset C of the vertices of a distance-regular graph is the maximum distance which occurs between elements of C. Dually, the dual width of a subset in a cometric association scheme is the index of the “last” eigenspace in the Q-polynomial ordering to which the characteristic vector of C is not orthogonal. Elementary bounds are derived on these two new parameters. We show that any...
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ژورنال
عنوان ژورنال: Journal of Combinatorial Theory, Series A
سال: 2012
ISSN: 0097-3165
DOI: 10.1016/j.jcta.2011.07.009