Results 21 to 30 of about 2,074 (148)
$H$-Chromatic Symmetric Functions [PDF]
The Electronic Journal of Combinatorics, 2022 We introduce $H$-chromatic symmetric functions, $X_{G}^{H}$, which use the $H$-coloring of a graph $G$ to define a generalization of Stanley's chromatic symmetric functions. We say two graphs $G_1$ and $G_2$ are $H$-chromatically equivalent if $X_{G_1}^{H} = X_{G_2}^{H}$, and use this idea to study uniqueness results for $H$-chromatic symmetric ...
Nancy Mae Eagles +4 more
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Chromatic quasisymmetric functions and noncommutative 𝑃-symmetric functions
Transactions of the American Mathematical SocietyFor a natural unit interval order P P , we describe proper colorings of the incomparability graph of
Hwang, Byung-Hak
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Scheduling Problems and Generalized Graph Coloring [PDF]
Discrete Mathematics & Theoretical Computer Science, 2020 We define a new type of vertex coloring which generalizes vertex coloring in graphs, hypergraphs, andsimplicial complexes. To this coloring there is an associated symmetric function in noncommuting variables for whichwe give a deletion-contraction ...
John Machacek
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A new two-variable generalization of the chromatic polynomial [PDF]
Discrete Mathematics & Theoretical Computer Science, 2003 We present a two-variable polynomial, which simultaneously generalizes the chromatic polynomial, the independence polynomial, and the matching polynomial of a graph.
Klaus Dohmen +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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Chromatic Bases for Symmetric Functions [PDF]
The Electronic Journal of Combinatorics, 2016 In this note we obtain numerous new bases for the algebra of symmetric functions whose generators are chromatic symmetric functions. More precisely, if $\{ G_ k \} _{k\geq 1}$ is a set of connected graphs such that $G_k$ has $k$ vertices for each $k$, then the set of all chromatic symmetric functions $\{ X_{G_ k} \} _{k\geq 1}$ generates the algebra of
Soojin Cho, Stephanie van Willigenburg
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Coloring Rings in Species [PDF]
Discrete Mathematics & Theoretical Computer Science, 2014 We present a generalization of the chromatic polynomial, and chromatic symmetric function, arising in the study of combinatorial species. These invariants are defined for modules over lattice rings in species.
Jacob White
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Structure and enumeration of $(3+1)$-free posets (extended abstract) [PDF]
Discrete Mathematics & Theoretical Computer Science, 2013 A poset is $(3+1)$-free if it does not contain the disjoint union of chains of length 3 and 1 as an induced subposet. These posets are the subject of the $(3+1)$-free conjecture of Stanley and Stembridge.
Mathieu Guay-Paquet +2 more
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Hecke algebra and quantum chromatic symmetric functions [PDF]
Discrete Mathematics & Theoretical Computer Science, 2012 We evaluate induced sign characters of $H_n(q)$ at certain elements of $H_n(q)$ and conjecture an interpretation for the resulting polynomials as generating functions for $P$-tableaux by a certain statistic.
Brittany Shelton, Mark Skandera
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The Chromatic Symmetric Function of a Graph Centred at a Vertex [PDF]
The Electronic Journal of Combinatorics, 2019 We discover new linear relations between the chromatic symmetric functions of certain sequences of graphs and apply these relations to find new families of $e$-positive unit interval graphs. Motivated by the results of Gebhard and Sagan, we revisit their ideas and reinterpret their equivalence relation in terms of a new quotient algebra of NCSym.
Farid Aliniaeifard +2 more
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