Cycle Double Covers and Semi-Kotzig Frame
arXiv:1105.5190 · doi:10.1016/j.ejc.2011.12.001
Abstract
Let be a cubic graph admitting a 3-edge-coloring such that the edges colored by 0 and induce a Hamilton circuit of and the edges colored by 1 and 2 induce a 2-factor . The graph is semi-Kotzig if switching colors of edges in any even subgraph of yields a new 3-edge-coloring of having the same property as . A spanning subgraph of a cubic graph is called a {\em semi-Kotzig frame} if the contracted graph is even and every non-circuit component of is a subdivision of a semi-Kotzig graph. In this paper, we show that a cubic graph has a circuit double cover if it has a semi-Kotzig frame with at most one non-circuit component. Our result generalizes some results of Goddyn (1988), and Häggkvist and Markström [J. Combin. Theory Ser. B (2006)].