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arXiv · 1402.2916

On the $f$-matching polytope and the fractional $f$-chromatic index

Stefan Glock
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Abstract

Our motivation is the question of how similar the $f$-colouring problem is to the classic edge-colouring problem, particularly with regard to graph parameters. In 2010, Zhang, Yu, and Liu gave a new description of the $f$-matching polytope and derived a formula for the fractional $f$-chromatic index, stating that the fractional $f$-chromatic index equals the maximum of the fractional maximum $f$-degree and the fractional $f$-density. Unfortunately, this formula is incorrect. We present counterexamples for both the description of the $f$-matching polytope and the formula for the fractional $f$-chromatic index. Finally, we prove a short lemma concerning the generalization of Goldberg's conjecture.

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Stefan Glock. 2014-02-12. On the $f$-matching polytope and the fractional $f$-chromatic index. https://arxiv.org/abs/1402.2916

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