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On centrally symmetric graphs

Manfred Stern (1996)

Mathematica Bohemica

In this note we extend results on the covering graphs of modular lattices (Zelinka) and semimodular lattices (Gedeonova, Duffus and Rival) to the covering graph of certain graded lattices.

On cyclically embeddable (n,n)-graphs

Agnieszka Görlich, Monika Pilśniak, Mariusz Woźniak (2003)

Discussiones Mathematicae Graph Theory

An embedding of a simple graph G into its complement G̅ is a permutation σ on V(G) such that if an edge xy belongs to E(G), then σ(x)σ(y) does not belong to E(G). In this note we consider the embeddable (n,n)-graphs. We prove that with few exceptions the corresponding permutation may be chosen as cyclic one.

On distances between isomorphism classes of graphs

Gerhard Benadé, Wayne Goddard, Terry A. McKee, Paul A. Winter (1991)

Mathematica Bohemica

In 1986, Chartrand, Saba and Zou [3] defined a measure of the distance between (the isomorphism classes of) two graphs based on 'edge rotations'. Here, that measure and two related measures are explored. Various bounds, exact values for classes of graphs and relationships are proved, and the three measures are shown to be intimately linked to 'slowly-changing' parameters.

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