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\(k\)-protected vertices in binary search trees. (English) Zbl 1281.05004

Summary: We show that for every \(k\), the probability that a randomly selected vertex of a random binary search tree on \(n\) nodes is at distance \(k-1\) from the closest leaf converges to a rational constant \(c_k\) as \(n\) goes to infinity.

MSC:

05A05 Permutations, words, matrices
05A15 Exact enumeration problems, generating functions
05A16 Asymptotic enumeration
05C30 Enumeration in graph theory
05C05 Trees
05C12 Distance in graphs
68P05 Data structures

References:

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