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{\bf {Elias M. Hagos }
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\noindent {\bf The characteristic polynomial of a graph is
reconstructible from the characteristic polynomials of its
vertex-deleted subgraphs and their complements} \vskip.5cm
The question of whether the characteristic polynomial of a simple
graph is uniquely determined by the characteristic polynomials of
its vertex-deleted subgraphs is one of the many unresolved
problems in graph reconstruction. In this paper we prove that the
characteristic polynomial of a graph is reconstructible from the
characteristic polynomials of the vertex-deleted subgraphs of the
graph and its complement.
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