An Algebraic Representation of Graphs and Applications to Graph Enumeration

<table>The linear combination of graphs obtained by applying the mapping <svg height="16.9" id="M759" style="vertical-align:-4.39398pt" version="1.1" viewbox="0 0 56.924999 16.9" width="56.924999" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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</svg> to the cutvertex of a graph consisting of two triangles sharing a vertex.</table>

International Journal of Combinatorics

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Figure 7

Figure 7: An Algebraic Representation of Graphs and Applications to Graph Enumeration 