اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدA tight ErdH{o}s-Posa function for wheel minors
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نشر من قبل
Jean-Florent Raymond
تاريخ النشر
2017
مجال البحث
الهندسة المعلوماتية
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English
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Let $W_t$ denote the wheel on $t+1$ vertices. We prove that for every integer $t geq 3$ there is a constant $c=c(t)$ such that for every integer $kgeq 1$ and every graph $G$, either $G$ has $k$ vertex-disjoint subgraphs each containing $W_t$ as minor, or there is a subset $X$ of at most $c k log k$ vertices such that $G-X$ has no $W_t$ minor. This is best possible, up to the value of $c$. We conjecture that the result remains true more generally if we replace $W_t$ with any fixed planar graph $H$.
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