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arXiv · 1309.0174

Further results on the nullity of signed graphs

Yu Liu·Lhua You
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Abstract

The nullity of a graph is the multiplicity of the eigenvalues zero in its spectrum. A signed graph is a graph with a sign attached to each of its edges. In this paper, we obtain the coefficient theorem of the characteristic polynomial of a signed graph, give two formulae on the nullity of signed graphs with cut-points. As applications of the above results, we investigate the nullity of the bicyclic signed graph $Γ(\infty(p,q,l))$, obtain the nullity set of unbalanced bicyclic signed graphs, and thus determine the nullity set of bicyclic signed graphs.

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Yu Liu, Lhua You. 2013-09-01. Further results on the nullity of signed graphs. https://arxiv.org/abs/1309.0174

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