Near Threshold Graphs

نویسنده

  • Steve Kirkland
چکیده

A conjecture of Grone and Merris states that for any graph G, its Laplacian spectrum, Λ(G), is majorized by its conjugate degree sequence, D∗(G). That conjecture prompts an investigation of the relationship between Λ(G) and D∗(G), and Merris has characterized the graphs G for which the multisets Λ(G) and D∗(G) are equal. In this paper, we provide a constructive characterization of the graphs G for which Λ(G) and D∗(G) share all but two elements.

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عنوان ژورنال:
  • Electr. J. Comb.

دوره 16  شماره 

صفحات  -

تاریخ انتشار 2009