Nullity of b-Bridge Coalescence Graphs

Authors

  • Khidir R. Sharaf Department of Mathematics, Faculty of Science, University of Zakho, Zakho, Kurdistan Region, Iraq. Author
  • Nechirvan B. Ibrahim Department of Mathematics, Faculty of Science, University of Zakho, Zakho, Kurdistan Region, Iraq. Author

DOI:

https://doi.org/10.17656/jzs.10461

Keywords:

Spectra of a Graph, Nullity of a Graph, b- Bridge Graphs

Abstract

The nullity η(G) (degree of singularity) of a graph G is the algebraic multiplicity of the
number zero in the spectrum of G. If G is a graph containing a vertex of degree one and
H be the subgraph obtained from G, by deleting this vertex together with the vertex
adjacent to it then, η(G) = η(H). In this paper, we proved that nullity of a graph is the
maximum number of independent variables in a high zero-sum weighting for it. The
above procedures are applied to evaluate the nullity of b-bridge coalescence graphs.
They are also applied to determine the nullity of edge introducing between t-tuple
coalescence graphs and nullity of paths introducing between (n, m)-tuples of coalescence
graphs.

References

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Published

2016-03-20

How to Cite

Nullity of b-Bridge Coalescence Graphs. (2016). Journal of Zankoy Sulaimani - Part A, 18(1), 167-178. https://doi.org/10.17656/jzs.10461