Weighted graphs: Eigenvalues and chromatic number
نویسنده
چکیده
We revisit Hoffman relation involving chromatic number χ and eigenvalues. We construct some graphs and weighted graphs such that the largest and smallest eigenvalues λ dan μ satisfy λ = (1 − χ)μ. We study in particular the eigenvalues of the integer simplex T 2 m, a 3-chromatic graph on ( m+2 2 ) vertices.
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ورودعنوان ژورنال:
- EJGTA
دوره 4 شماره
صفحات -
تاریخ انتشار 2016