Fixed-Parameter Algorithms for Longest Heapable Subsequence and Maximum Binary Tree

@article{Chandrasekaran2021FixedParameterAF,
  title={Fixed-Parameter Algorithms for Longest Heapable Subsequence and Maximum Binary Tree},
  author={Karthekeyan Chandrasekaran and Elena Grigorescu and Gabriel Istrate and Shubhang Kulkarni and Young-San Lin and Minshen Zhu},
  journal={ArXiv},
  year={2021},
  volume={abs/2110.00495}
}
A heapable sequence is a sequence of numbers that can be arranged in a min-heap data structure. Finding a longest heapable subsequence of a given sequence was proposed by Byers, Heeringa, Mitzenmacher, and Zervas (ANALCO 2011) as a generalization of the well-studied longest increasing subsequence problem and its complexity still remains open. An equivalent formulation of the longest heapable subsequence problem is that of finding a maximum-sized binary tree in a given permutation directed… 

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