Improved product structure for graphs on surfaces

نویسندگان

چکیده

Dujmovi\'c, Joret, Micek, Morin, Ueckerdt and Wood [J. ACM 2020] proved that for every graph $G$ with Euler genus $g$ there is a $H$ treewidth at most 4 path $P$ such $G\subseteq H \boxtimes P K_{\max\{2g,3\}}$. We improve this result by replacing "4" "3" planar. in fact prove more general terms of so-called framed graphs. This implies $(g,d)$-map contained $ P\boxtimes K_\ell$, some planar $3$, where $\ell=\max\{2g\lfloor \frac{d}{2} \rfloor,d+3\lfloor\frac{d}{2}\rfloor-3\}$. It also $(g,1)$-planar (that is, graphs can be drawn surface one crossing per edge) $H\boxtimes K_{\max\{4g,7\}}$, $3$.

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ژورنال

عنوان ژورنال: Discrete Mathematics & Theoretical Computer Science

سال: 2022

ISSN: ['1365-8050', '1462-7264']

DOI: https://doi.org/10.46298/dmtcs.8877