Afrika Matematika

, Volume 29, Issue 3–4, pp 499–507 | Cite as

Skew Laplacian energy of digraphs

  • Hilal A. Ganie
  • Bilal A. Chat


In this paper, we consider the Laplacian energy of digraphs. Various approaches for the Laplacian energy of a digraph have been put forward by different authors. We consider the skew Laplacian energy of a digraph as given in Cai et al. (Trans Combin 2:27–37, 2013). We obtain some upper and lower bounds for the skew Laplacian energy which are better than some previous known bounds. We also show every even positive integer is the skew Laplacian energy of some digraphs.


Laplacian spectra Skew-Laplacian spectra Skew-Laplacian energy of a diagraph 

Mathematics Subject Classification

05C50 05C30 



The authors would like to express their sincere thanks and gratitude to their Ph.D advisor Prof. S. Pirzada and one of his students Dr. Mushtaq Ahmad for their help and useful suggestions throughout the work.


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Copyright information

© African Mathematical Union and Springer-Verlag GmbH Deutschland, ein Teil von Springer Nature 2018

Authors and Affiliations

  1. 1.Department of MathematicsUniversity of KashmirSrinagarIndia
  2. 2.Department of MathematicsCentral University of KashmirSrinagarIndia

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