un 2 00 9 Note for Nikiforov ’ s two conjectures on the energy of trees ∗
نویسندگان
چکیده
The energy E of a graph is defined to be the sum of the absolute values of its eigenvalues. Nikiforov in “V. Nikiforov, The energy of C4-free graphs of bounded degree, Lin. Algebra Appl. 428(2008), 2569–2573” proposed two conjectures concerning the energy of trees with maximum degree ∆ ≤ 3. In this short note, we show that both conjectures are true.
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