Results 41 to 50 of about 568,566 (214)
Recursion Relations for Chromatic Coefficients for Graphs and Hypergraphs
Discussiones Mathematicae Graph Theory, 2022 We establish a set of recursion relations for the coefficients in the chromatic polynomial of a graph or a hypergraph. As an application we provide a generalization of Whitney’s broken cycle theorem for hypergraphs, as well as deriving an explicit ...
Durhuus Bergfinnur, Lucia Angelo
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Melting lollipop chromatic quasisymmetric functions and Schur expansion of unicellular LLT polynomials [PDF]
Discrete Mathematics, 2018 In this work, we generalize and utilize the linear relations of LLT polynomials introduced by Lee \cite{Lee}. By using the fact that the chromatic quasisymmetric functions and the unicellular LLT polynomials are related via plethystic substitution and ...
JiSun Huh, Sun-Young Nam, Meesue Yoo
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Chromatic nonsymmetric polynomials of Dyck graphs are slide-positive [PDF]
Proceedings of the American Mathematical Society, 2019 Motivated by the study of Macdonald polynomials, J. Haglund and A. Wilson introduced a nonsymmetric polynomial analogue of the chromatic quasisymmetric function called the chromatic nonsymmetric polynomial of a Dyck graph.
V. Tewari, A. Wilson, Philip B. Zhang
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Worpitzky-compatible subarrangements of braid arrangements and cocomparability graphs
Comptes Rendus. Mathématique, 2021 The class of Worpitzky-compatible subarrangements of a Weyl arrangement together with an associated Eulerian polynomial was recently introduced by Ashraf, Yoshinaga and the first author, which brings the characteristic and Ehrhart quasi-polynomials into ...
Tran, Tan Nhat, Tsuchiya, Akiyoshi
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Burnside Chromatic Polynomials of Group-Invariant Graphs
Discussiones Mathematicae Graph Theory, 2023 We introduce the Burnside chromatic polynomial of a graph that is invariant under a group action. This is a generalization of the Q-chromatic function Zaslavsky introduced for gain graphs.
White Jacob A.
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Zero-Free Intervals of Chromatic Polynomials of Mixed Hypergraphs
Mathematics, 2022 A mixed hypergraph H is a triple (X,C,D), where X is a finite set and each of C and D is a family of subsets of X. For any positive integer λ, a proper λ-coloring of H is an assignment of λ colors to vertices in H such that each member in C contains at ...
Ruixue Zhang +2 more
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Acyclic orientation polynomials and the sink theorem for chromatic symmetric functions [PDF]
J. Comb. Theory B, 2019 We define the acyclic orientation polynomial of a graph to be the generating function for the sinks of its acyclic orientations. Stanley proved that the number of acyclic orientations is equal to the chromatic polynomial evaluated at $-1$ up to sign ...
Byung-Hak Hwang +4 more
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More connections between the matching polynomial and the chromatic polynomial
AKCE International Journal of Graphs and Combinatorics, 2019 The connection between the matching polynomial and the chromatic polynomial for triangle-free graphs was revealed in the work of Farrell and Whitehead. We extend this result to all graph by mirroring the corresponding result of Godsil and Gutman for the ...
Beatriz Carely Luna-Olivera +2 more
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A Symmetric Function of Increasing Forests
Forum of Mathematics, Sigma, 2021 For an indifference graph G, we define a symmetric function of increasing spanning forests of G. We prove that this symmetric function satisfies certain linear relations, which are also satisfied by the chromatic quasisymmetric function and unicellular $\
Alex Abreu, Antonio Nigro
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Combinatorics of certain abelian Lie group arrangements and chromatic quasi-polynomials [PDF]
Journal of Combinatorial Theory, 2018 The purpose of this paper is twofold. Firstly, we generalize the notion of characteristic polynomials of hyperplane and toric arrangements to those of certain abelian Lie group arrangements.
T. Tran, M. Yoshinaga
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