On Q-Polynomial Association Schemes of Small Class
نویسنده
چکیده
We show an inequality involving the third largest or second smallest dual eigenvalues of Q-polynomial association schemes of class at least three. Also we characterize dual-tight Q-polynomial association schemes of class three. Our method is based on tridiagonal matrices and can be applied to distance-regular graphs as well.
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عنوان ژورنال:
- Electr. J. Comb.
دوره 19 شماره
صفحات -
تاریخ انتشار 2012