The smallest eigenvalues of Hamming graphs, Johnson graphs and other distance-regular graphs with classical parameters
نویسندگان
چکیده
We prove a conjecture by Van Dam & Sotirov on the smallest eigenvalue of (distance-j) Hamming graphs and a conjecture by Karloff on the smallest eigenvalue of (distance-j) Johnson graphs. More generally, we study the smallest eigenvalue and the second largest eigenvalue in absolute value of the graphs of the relations of classical P and Q-polynomial association schemes.
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ورودعنوان ژورنال:
- CoRR
دوره abs/1709.09011 شماره
صفحات -
تاریخ انتشار 2017