Mixed Energy of a Mixed Hourglass Graph


  • Olayiwola Babarinsa Department of Mathematical Sciences, Federal University Lokoja, 1154 Kogi State
  • Hailiza Kamarulhaili School of Mathematical Sciences, Universiti Sains Malaysia, 11800 Pulau Pinang




Hourglass matrix, Adjacency matrix, Mixed graph, Mixed energy


In this paper we discuss a complete mixed graph called mixed hourglass graph. The direct representation of hourglass matrix in graph gives a weighted mixed hourglass graph. Then, we obtain a mixed hourglass graph from the weighted mixed hourglass graph by assigning its edge-labelled a numerical value of weight 1. Next, we derive the determinant, spectrum and mixed energy of the graph to conclude that the energy of a mixed hourglass graph coincides with twice the number of edges in the graph and the sum of the square of its eigenvalues.


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How to Cite

Babarinsa, O., & Kamarulhaili, H. (2019). Mixed Energy of a Mixed Hourglass Graph. Communications in Mathematics and Applications, 10(1), 45–53. https://doi.org/10.26713/cma.v10i1.1143



Research Article