Isomorphism Testing and Canonical Forms for k-Contractable Graphs (A Generalization of Bounded Valence and Bounded Genus)
نویسنده
چکیده
A polynomial time isomorphism test for graphs called k-contractible graphs for fixed k is included. The class of k-contractible graphs includes the graphs of bounded valence and the graphs of bounded genus. The algorithm several new ideas including: (1) It removes portions of the graph and replaces them with groups which are used to keep track of the symmetries of these portions. (2) It maintains with each group a tower of equivalence relations which allow a decomposition of the group. These towers are called towers of
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