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Long properly coloured cycles in edge-coloured graphs

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 نشر من قبل Allan Lo
 تاريخ النشر 2018
  مجال البحث
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 تأليف Allan Lo




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Let $G$ be an edge-coloured graph. The minimum colour degree $delta^c(G)$ of $G$ is the largest integer $k$ such that, for every vertex $v$, there are at least $k$ distinct colours on edges incident to $v$. We say that $G$ is properly coloured if no two adjacent edges have the same colour. In this paper, we show that, for any $varepsilon >0$ and $n$ large, every edge-coloured graph $G$ with $delta^c(G) ge (1/2+varepsilon)n$ contains a properly coloured cycle of length at least $min{ n , lfloor 2 delta^c(G)/3 rfloor}$.

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