activity
20152025
most citedOn universal partial words

5 citations · 8 across the 8 of their papers we have counts for

collaborators

9 papers

math.CO2025

Efficient k-mer Dataset Compression Using Eulerian Covers of de Bruijn Graphs and BWT

H. Z. Q. Chen, S. Kitaev, X. Lang +2

Transforming an input sequence into its constituent k-mers is a fundamental operation in computational genomics. To reduce storage costs associated with k-mer datasets, we introduc…

math.CO2025

On the word-representability of - graphs

Herman Z. Q. Chen, Humaira Hameed, Sergey Kitaev

Word-representable graphs are a class of graphs that can be represented by words, where edges and non-edges are determined by the alternation of letters in those words. Several pap…

math.CO2019

Representing split graphs by words

Herman Z. Q. Chen, Sergey Kitaev, Akira Saito

There is a long line of research in the literature dedicated to word-representable graphs, which generalize several important classes of graphs. However, not much is known about wo…

math.CO2019

On the probability of existence of a universal cycle or a universal word for a set of words

Herman Z. Q. Chen, Sergey Kitaev, Brian Y. Sun

A universal cycle, or u-cycle, for a given set of words is a circular word that contains each word from the set exactly once as a contiguous subword. The celebrated de Bruijn seque…

math.CO2016

The unimodality of the Ehrhart -polynomial of the chain polytope of the zig-zag poset

Herman Z. Q. Chen, Philip B. Zhang

We prove the unimodality of the Ehrhart -polynomial of the chain polytope of the zig-zag poset, which was conjectured by Kirillov. First, based on a result due to Stanley, we sh…

math.CO2016★ 2 cited

The Real-rootedness of Generalized Narayana Polynomials

Herman Z. Q. Chen, Arthur L. B. Yang, Philip B. Zhang

In this paper, we prove the real-rootedness of two classes of generalized Narayana polynomials: one arising as the -polynomials of the generalized associahedron associated to th…

math.CO2016

Kirillov's unimodality conjecture for the rectangular Narayana polynomials

Herman Z. Q. Chen, Arthur L. B. Yang, Philip B. Zhang

In the study of Kostka numbers and Catalan numbers, Kirillov posed a unimodality conjecture for the rectangular Narayana polynomials. We prove that the rectangular Narayana polynom…

math.CO2016★ 5 cited

On universal partial words

Herman Z. Q. Chen, Sergey Kitaev, Torsten Mütze +1

A universal word for a finite alphabet and some integer is a word over such that every word in appears exactly once as a subword (cyclically or linearly). I…

math.CO2015★ 1 cited

Word-representability of triangulations of grid-covered cylinder graphs

Thomas Z. Q. Chen, Sergey Kitaev, Brian Y. Sun

A graph is word-representable if there exists a word over the alphabet such that letters and , , alternate in if and only if . Hal…