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arXiv · 0810.1979

Markov bases of binary graph models of K_4-minor free graphs

Daniel Král'·Serguei Norine·Ondrej Pangrác
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Abstract

Markov width of a graph is a graph invariant defined as the maximum degree of a Markov basis element for the corresponding graph model for binary contingency tables. We show that a graph has Markov width at most four if and only if it contains no $K_4$ as a minor, answering a question of Develin and Sullivant. We also present a lower bound of order $Ω(n^{2-\varepsilon})$ on the Markov width of $K_n$.

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Daniel Král', Serguei Norine, Ondrej Pangrác. 2008-10-10. Markov bases of binary graph models of K_4-minor free graphs. https://arxiv.org/abs/0810.1979

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