Bounds on graph eigenvalues II
نویسنده
چکیده
We prove three results about the spectral radius μ (G) of a graph G : (a) Let Tr (n) be the r-partite Turán graph of order n. If G is a Kr+1-free graph of order n, then μ (G) < μ (Tr (n)) unless G = Tr (n) . (b) For most irregular graphs G of order n and size m, μ (G)− 2m/n > 1/ (2m+ 2n) . (c) Let 0 ≤ k ≤ l. If G is a graph of order n with no K2 +Kk+1 and no K2,l+1, then μ (G) ≤ min {
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