On a Class of Extremal Trees for Various Indices

نویسنده

  • CLEMENS HEUBERGER
چکیده

It was recently shown that an interesting class of trees maximizes the MerrifieldSimmons index and minimizes the Hosoya index and energy among all trees with given number of vertices and maximum degree. In this paper, we describe how these trees (which we will call F-trees) can be constructed algorithmically by means of so-called F-expansions, which are very similar to ordinary base-d digital expansions. Our algorithms are illustrated by various examples. Furthermore, some more properties of F-trees are described and numerical data is provided.

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تاریخ انتشار 2008