Partial Characterizations of Circle Graphs
نویسندگان
چکیده
A circle graph is the intersection graph of a family of chords on a circle. There is no known characterization of circle graphs by forbidden induced subgraphs that do not involve the notions of local equivalence or pivoting operations. We characterize circle graphs by a list of minimal forbidden induced subgraphs when the graph belongs to one of the following classes: linear domino graphs, P4-tidy graphs, and tree-cographs. We also completely characterize by minimal forbidden induced subgraphs the class of unit Helly circle graphs, which are those circle graphs having a model whose chords have all the same length, are pairwise different, and satisfy the Helly property.
منابع مشابه
Isotropic Matroids II: Circle Graphs
We present several characterizations of circle graphs, which follow from Bouchet’s circle graph obstructions theorem.
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