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One more Turan number and Ramsey number for the loose 3-uniform path of length three

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 نشر من قبل Joanna Polcyn
 تاريخ النشر 2015
  مجال البحث
والبحث باللغة English
 تأليف Joanna Polcyn




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Let $P$ denote a 3-uniform hypergraph consisting of 7 vertices $a,b,c,d,e,f,g$ and 3 edges ${a,b,c}, {c,d,e},$ and ${e,f,g}$. It is known that the $r$-color Ramsey number for $P$ is $R(P;r)=r+6$ for $rle 9$. The proof of this result relies on a careful analysis of the Turan numbers for $P$. In this paper, we refine this analysis further and compute the fifth order Turan number for $P$, for all $n$. Using this number for $n=16$, we confirm the formula $R(P;10)=16$.



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