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We extend the definition of the chromatic symmetric function $X_G$ to include graphs $G$ with a vertex-weight function $w : V(G) \rightarrow \mathbb{N}$. We show how this provides the chromatic symmetric function with a natural…

Combinatorics · Mathematics 2020-01-16 Logan Crew , Sophie Spirkl

For a graph $G$, its Tutte symmetric function $XB_G$ generalizes both the Tutte polynomial $T_G$ and the chromatic symmetric function $X_G$. We may also consider $XB$ as a map from the $t$-extended Hopf algebra $\mathbb{G}[t]$ of labelled…

Combinatorics · Mathematics 2021-12-09 Logan Crew , Sophie Spirkl

We define a new type of vertex coloring which generalizes vertex coloring in graphs, hypergraphs, and simplicial complexes. This coloring also generalizes oriented coloring, acyclic coloring, and star coloring. There is an associated…

Combinatorics · Mathematics 2020-01-22 John Machacek

Stanley [9] introduced the chromatic symmetric function ${\bf X}_G$ associated to a simple graph $G$ as a generalization of the chromatic polynomial of $G$. In this paper we present a novel technique to write ${\bf X}_G$ as a linear…

Combinatorics · Mathematics 2013-08-29 Rosa Orellana , Geoffrey Scott

We focus on two specific generalizations of the chromatic symmetric function: one involving universal graphs and the other concerning vertex-weighted graphs. In this paper, we introduce a unified generalization that incorporates both…

Combinatorics · Mathematics 2025-04-01 Yosuke Sato

We prove a general inclusion-exclusion relation for the extended chromatic symmetric function of a weighted graph, which specializes to (extended) $k$-deletion, and we give two methods to obtain numerous new bases from weighted graphs for…

Combinatorics · Mathematics 2021-03-29 Farid Aliniaeifard , Victor Wang , Stephanie van Willigenburg

Crew and Spirklt generalize Stanley's chromatic symmetric function to vertex-weighted graphs. One of the primary motivations for extending the chromatic symmetric function to vertex-weighted graphs is the existence of a deletion-contraction…

Combinatorics · Mathematics 2023-08-08 Azzurra Ciliberti

We take an elementary and systematic approach to the problem of extending the Tutte polynomial to the setting of embedded graphs. Four notions of embedded graphs arise naturally when considering deletion and contraction operations on graphs…

Combinatorics · Mathematics 2023-01-02 Stephen Huggett , Iain Moffatt

In this paper, we extend the chromatic symmetric function $X$ to a chromatic $k$-multisymmetric function $X_k$, defined for graphs equipped with a partition of their vertex set into $k$ parts. We demonstrate that this new function retains…

Combinatorics · Mathematics 2022-09-29 Logan Crew , Evan Haithcock , Josephine Reynes , Sophie Spirkl

Richard Stanley defined the chromatic symmetric function $X_G$ of a graph $G$ and asked whether there are non-isomorphic trees $T$ and $U$ with $X_T=X_U$. We study variants of the chromatic symmetric function for rooted graphs, where we…

Combinatorics · Mathematics 2023-04-12 Nicholas A. Loehr , Gregory S. Warrington

In this paper, we introduce and study two variants of the chromatic quasisymmetric function of a graph: the total chromatic quasisymmetric function via vertex labeling and via acyclic orientations. The original definition of the chromatic…

Combinatorics · Mathematics 2026-02-27 Laura Colmenarejo , Ian Klein

A MacMahon symmetric function is an invariant of the diagonal action of the symmetric group on power series in multiple alphabets of variables. We introduce an analogue of the chromatic symmetric function for vertex-weighted graphs, taking…

Combinatorics · Mathematics 2025-08-04 Jeremy L. Martin , May B. Trist

We prove some Schur positivity results for the chromatic symmetric function $X_G$ of a (hyper)graph $G$, using connections to the group algebra of the symmetric group. The first such connection works for (hyper)forests $F$: we describe the…

Combinatorics · Mathematics 2024-10-29 Brendan Pawlowski

The deletion--contraction algorithm is perhaps the most popular method for computing a host of fundamental graph invariants such as the chromatic, flow, and reliability polynomials in graph theory, the Jones polynomial of an alternating…

Data Structures and Algorithms · Computer Science 2008-04-14 Andreas Björklund , Thore Husfeldt , Petteri Kaski , Mikko Koivisto

The chromatic symmetric function $X_G$ is a sum of monomials corresponding to proper vertex colorings of a graph $G$. Crew, Pechenik, and Spirkl (2023) recently introduced a $K$-theoretic analogue $\overline{X}_G$ called the Kromatic…

Combinatorics · Mathematics 2025-02-21 Laura Pierson

Tutte's dichromate T(x,y) is a well known graph invariant. Using the original definition in terms of internal and external activities as our point of departure, we generalize the valuations T(x,1) and T(1,y) to hypergraphs. In the…

Combinatorics · Mathematics 2011-03-08 Tamás Kálmán

We define vertex-colourings for edge-partitioned digraphs, which unify the theory of P-partitions and proper vertex-colourings of graphs. We use our vertex-colourings to define generalized chromatic functions, which merge the chromatic…

Combinatorics · Mathematics 2023-06-28 Farid Aliniaeifard , Shu Xiao Li , Stephanie van Willigenburg

The Tutte polynomial is a fundamental invariant of graphs. In this article, we define and study a generalization of the Tutte polynomial for directed graphs, that we name B-polynomial. The B-polynomial has three variables, but when…

Combinatorics · Mathematics 2019-01-01 Jordan Awan , Olivier Bernardi

In this paper, we introduce the concept of the weighted (harmonic) chromatic polynomials of graphs and discuss some of its properties. We also present the notion of the weighted (harmonic) Tutte--Grothendieck polynomials of graphs and give…

Combinatorics · Mathematics 2023-07-03 Himadri Shekhar Chakraborty , Tsuyoshi Miezaki , Chong Zheng

Stanley associated with a graph G a symmetric function X_G which reduces to G's chromatic polynomial under a certain specialization of variables. He then proved various theorems generalizing results about the chromatic polynomial, as well…

Combinatorics · Mathematics 2007-05-23 David D. Gebhard , Bruce E. Sagan
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