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Flexibility of planar graphs without $C_4$ and $C_5$

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 نشر من قبل Donglei Yang
 تاريخ النشر 2020
  مجال البحث
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Let $G$ be a ${C_4, C_5}$-free planar graph with a list assignment $L$. Suppose a preferred color is given for some of the vertices. We prove that if all lists have size at least four, then there exists an $L$-coloring respecting at least a constant fraction of the preferences.



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