Maxima of the Q-index: degenerate graphs

نویسندگان

  • Vladimir Nikiforov
  • VLADIMIR NIKIFOROV
چکیده

Let G be a k-degenerate graph of order n. It is well-known that G has no more edges than Sn,k, the join of a complete graph of order k and an independent set of order n−k. In this note, it is shown that Sn,k is extremal for some spectral parameters of G as well. More precisely, letting μ (H) and q (H) denote the largest eigenvalues of the adjacency matrix and the signless Laplacian of a graph H, the inequalities μ (G) < μ (

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تاریخ انتشار 2014