Enumerations of 3 di-sk trees

Abstract

Abstract: The study investigates several counting problems related to 3 di-sk trees, which are characterized as a hybrid ternary tree without the left edge labeled (2,2). Obtaining several enumeration results with respect to certain statistics of 3 di-sk trees. A bijection between the set of all 3 di-sk trees with n internal nodes and the set of all 3-Schröder paths from (0,0) to (3n,0) is given.

Key words: hybrid ternary trees, 3 di-sk trees, 3-Schröder paths, bijection

CLC Number:

O157.1

TIAN Zhen-ji, DOU Shu-ping. Enumerations of 3 di-sk trees[J]. Journal of Lanzhou University of Technology, 2024, 50(6): 144-149.

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URL: https://journal.lut.edu.cn/EN/

https://journal.lut.edu.cn/EN/Y2024/V50/I6/144

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