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Spanning Trails with Maximum Degree at Most 4 in \(2K_2\)-Free Graphs

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Abstract

A graph is called \(2K_2\)-free if it does not contain two independent edges as an induced subgraph. Gao and Pasechnik conjectured that every \(\frac{3}{2}\)-tough \(2K_2\)-free graph with at least three vertices has a spanning trail with maximum degree at most 4. In this paper, we confirm this conjecture. We also provide examples for all \(t < \frac{5}{4}\) of t-tough graphs that do not have a spanning trail with maximum degree at most 4.

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Correspondence to Songling Shan.

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M. N. Ellingham: Supported by Simons Foundation award 429625.

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Chen, G., Ellingham, M.N., Saito, A. et al. Spanning Trails with Maximum Degree at Most 4 in \(2K_2\)-Free Graphs. Graphs and Combinatorics 33, 1095–1101 (2017). https://doi.org/10.1007/s00373-017-1823-2

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  • DOI: https://doi.org/10.1007/s00373-017-1823-2

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