2019. 02. 21. 12:10 - 2019. 02. 21. 13:40
             MTA Rényi Intézet, nagyterem
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    Esemény típusa:
              szeminárium
          
             
  
    Szervezés:
              Intézeti
          
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             Extremális halmazrendszerek szeminárium
          Leírás
Let $F(n,k)$ ($f(n,k)$) denote the maximum possible size of the smallest color class in a (partial) $k$-coloring of the Boolean lattice $B_n$ that does not admit a rainbow antichain of size $k$. The value of $F(n,3)$ and $f(n,2)$ has been recently determined exactly. We prove that for any fixed $k$ if $n$ is large enough, then $F(n,k),f(n,k)=2^{(1/2+o(1))n}$ holds.
    
    We also introduce the general functions for any poset $P$ and integer $c\ge |P|$: let $F(n,c,P)$ ($f(n,c,P)$) denote the the maximum possible size of the smallest color class in a (partial) $c$-coloring of the Boolean lattice $B_n$ that does not admit a rainbow copy of $P$. We consider the first instances of this general problem.