Proyecciones Journal of Mathematics Vol. 31, N^o 3, pp. 247-259, September 2012. Universidad Católica del Norte Antofagasta - Chile

 

On the spectral radius of weighted digraphs

Ç. Burcu

Selçuk University, Turkey

Durmus Bozkurt

Selçuk University, Turkey

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ABSTRACT

We consider the weighted digraphs in which the arc weights are positive definite matrices. We obtain some upper bounds for the spectral radius of these digraphs and characterize the digraphs achieving the upper bounds. Some known upper bounds are then special cases of our results.

Keywords : Weighted digraph, spectral radius, upper bound.

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§. Burcu Bozkurt

Department of Mathematics, Science Faculty, Selçuk University,

42075, Konya,

Turkey

e-mail : sbbozkurt@selcuk.edu.tr and

Durmu§Bozkurt

Department of Mathematics, Science Faculty, Selçuk University,

42075, Konya,

Turkey

e-mail : dbozkurt@selcuk.edu.tr

Received : March 2012. Accepted : June 2012