Two-graphs, Double Covers over Complete Graphs, and Almost Self-complementary Graphs
نویسندگان
چکیده
A graph X is called almost self-complementary with respect to a perfect matching I in the complement Xc if it is isomorphic to the graph obtained from Xc by removing the edges of I. In this paper we investigate the relationship between self-complementary two-graphs and double covers over complete graphs that are almost self-complementary with respect to their set of fibres. In particular, we classify all doubly transitive selfcomplementary two-graphs, and therefore all almost self-complementary graphs with an automorphism group acting 2-transitively on the corresponding perfect matching.
منابع مشابه
European Journal of Combinatorics
A graph X is called almost self-complementary with respect to a perfect matching I if it is isomorphic to the graph obtained from its complement Xc by removing the edges of I. A two-graph on a vertex set Ω is a collection T of 3-subsets of Ω such that each 4-subset of Ω contains an even number of elements of T . In this paper we investigate the relationship between self-complementary two-graphs...
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