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arXiv · 1104.0003

On a connection between the switching separability of a graph and that of its subgraphs

Denis Krotov
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Abstract

A graph of order $n>3$ is called {switching separable} if its modulo-2 sum with some complete bipartite graph on the same set of vertices is divided into two mutually independent subgraphs, each having at least two vertices. We prove the following: if removing any one or two vertices of a graph always results in a switching separable subgraph, then the graph itself is switching separable. On the other hand, for every odd order greater than 4, there is a graph that is not switching separable, but removing any vertex always results in a switching separable subgraph. We show a connection with similar facts on the separability of Boolean functions and reducibility of $n$-ary quasigroups. Keywords: two-graph, reducibility, separability, graph switching, Seidel switching, graph connectivity, $n$-ary quasigroup

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Denis Krotov. 2011-03-31. On a connection between the switching separability of a graph and that of its subgraphs. https://doi.org/10.1134/s1990478911020116

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