A Spectral Equivalent Condition of the $P$-Polynomial Property for Association Schemes
نویسندگان
چکیده
منابع مشابه
A Spectral Equivalent Condition of the P-polynomial Property for Association Schemes
We give two equivalent conditions of the P -polynomial property of a symmetric association scheme. The first equivalent condition shows that the P -polynomial property is determined only by the first and second eigenmatrices of the symmetric association scheme. The second equivalent condition is another expression of the first using predistance polynomials.
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Gardiner [5] and Bannai and Bannai [1] classified symmetric association schemes (X, {Ro, ... , Rd}) such that for (at least) two different choices of i, the graph (X, Ri ) is distance-regular with diameter d. It turns out that except in the case of a polygon there are never more than two choices for i. Let one of the choices be i = 1, and let the ordering of the relations be such that R j is th...
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ژورنال
عنوان ژورنال: The Electronic Journal of Combinatorics
سال: 2014
ISSN: 1077-8926
DOI: 10.37236/4423