Bell Graphs are Determined by their Laplacian Spectra

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Authors: A. Z. ABDIAN

DOI: 10.46793/KgJMat2302.203A


A graph G is said to be determined by the spectrum of its Laplacian spectrum (DLS, for short) if every graph with the same spectrum is isomorphic to G. An -graph is a graph consisting of two cycles with just a vertex in common. Consider the coalescence of an -graph and the star graph K1,s, with respect to their unique maximum degree. We call this a bell graph. In this paper, we aim to prove that all bell graphs are DLS.


Bell graph, Laplacian spectrum, L-cospectral, cospectral graphs, spectral characterization.


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