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The energy of C4-free graphs of bounded degree

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 نشر من قبل Vladimir Nikiforov
 تاريخ النشر 2021
  مجال البحث
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Answering some questions of Gutman, we show that, except for four specific trees, every connected graph G of order n, with no cycle of order 4 and with maximum degree at most 3, has energy greater that its order. Here, the energy of a graph is the sum of the moduli of its eigenvalues. We give more general theorems and state two conjectures.

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