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Inducibility of 4-vertex tournaments

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 نشر من قبل Michael Phillips
 تاريخ النشر 2021
  مجال البحث
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We determine the inducibility of all tournaments with at most $4$ vertices together with the extremal constructions. The $4$-vertex tournament containing an oriented $C_3$ and one source vertex has a particularly interesting extremal construction. It is an unbalanced blow-up of an edge, where the sink vertex is replaced by a quasi-random tournament and the source vertex is iteratively replaced by a copy of the construction itself.



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