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Some extremal ratios of the distance and subtree problems in binary trees

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 نشر من قبل Shujing Wang
 تاريخ النشر 2017
  مجال البحث
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Among many topological indices of trees the sum of distances $sigma(T)$ and the number of subtrees $F(T)$ have been a long standing pair of graph invariants that are well known for their negative correlation. That is, among various given classes of trees, the extremal structures maximizing one usually minimize the other, and vice versa. By introducing the local



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