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Refined enumeration of vertices among all rooted ordered $d$-trees

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 نشر من قبل Heesung Shin
 تاريخ النشر 2018
  مجال البحث
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In this paper we enumerate the cardinalities for the set of all vertices of outdegree $ge k$ at level $ge ell$ among all rooted ordered $d$-trees with $n$ edges. Our results unite and generalize several previous works in the literature.



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