On the Energy of Digraphs
نویسندگان
چکیده
The energy of a digraph D with eigenvalues z1, z2, . . . , zn is defined as E(D) = n ∑ j=1 |Rzj |, where Rzj is the real part of the complex number zj . In this paper, we characterize some positive reals that cannot be the energy of a digraph. We also obtain a sharp lower bound for the energy of strongly connected digraphs.
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