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Most results on the value sets $V_f$ of polynomials $f \in \mathbb{F}_q[x]$ relate the cardinality $|V_f|$ to the degree of $f$. In particular, the structure of the spectrum of the class of polynomials of a fixed degree $d$ is rather well…

Combinatorics · Mathematics 2017-01-24 Leyla Işık , Alev Topuzoğlu

The independence polynomial of a graph is the generating polynomial for the number of independent sets of each size, and its roots are called {\em independence roots}. We investigate the stability of such polynomials, that is, conditions…

Combinatorics · Mathematics 2018-02-08 Jason Brown , Ben Cameron

Partial cubes are the graphs which can be embedded into hypercubes. The {\em cube polynomial} of a graph $G$ is a counting polynomial of induced hypercubes of $G$, which is defined as $C(G,x):=\sum_{i\geqslant 0}\alpha_i(G)x^i$, where…

Combinatorics · Mathematics 2024-06-18 Yan-Ting Xie , Yong-De Feng , Shou-Jun Xu

An independent set in a graph is a set of pairwise non-adjacent vertices, and a(G) is the size of a maximum independent set in the graph G. If s_{k} is the number of independent sets of cardinality k in G, then…

Discrete Mathematics · Computer Science 2013-03-12 Vadim E. Levit , Eugen Mandrescu

In a finite undirected simple graph, a chordless cycle is an induced subgraph which is a cycle. A graph is called cyclically orientable if it admits an orientation in which every chordless cycle is cyclically oriented. We propose an…

Data Structures and Algorithms · Computer Science 2015-05-13 Elisângela Silva Dias , Diane Castonguay

For a class $\mathcal{G}$ of graphs, the objective of \textsc{Subgraph Complementation to} $\mathcal{G}$ is to find whether there exists a subset $S$ of vertices of the input graph $G$ such that modifying $G$ by complementing the subgraph…

Data Structures and Algorithms · Computer Science 2023-03-29 Dhanyamol Antony , Sagartanu Pal , R. B. Sandeep

An ordinal-valued metric taking its values in the set of all countable ordinals can be assigned to a metrizable set of nodes in a transfinite graph. Then, a variety of results concerning nodal eccentricities, radii, diameters, centers,…

Combinatorics · Mathematics 2007-05-23 A. H. Zemanian

A graph polynomial $P$ is weakly distinguishing if for almost all finite graphs $G$ there is a finite graph $H$ that is not isomorphic to $G$ with $P(G)=P(H)$. It is weakly distinguishing on a graph property $\mathcal{C}$ if for almost all…

Combinatorics · Mathematics 2020-10-21 Johann A. Makowsky , Vsevolod Rakita

We classify the countable homogeneous coloured multipartite graphs with any finite number of parts. By Fraisse's Theorem this amounts to classifying the families F of pairwise non-embeddable finite coloured multipartite graphs for which the…

Combinatorics · Mathematics 2014-06-26 Deborah C Lockett , John K Truss

A graph $G$ is said to be an $(s, k)$-polar graph if its vertex set admits a partition $(A, B)$ such that $A$ and $B$ induce, respectively, a complete $s$-partite graph and the disjoint union of at most $k$ complete graphs. Polar graphs and…

Combinatorics · Mathematics 2024-10-16 Fernando Esteban Contreras-Mendoza , César Hernández-Cruz

In this paper, we introduce a new concept namely degree polynomial for vertices of a simple graph. This notion leads to a concept namely degree polynomial sequence which is stronger than the concept of degree sequence. After obtaining the…

Combinatorics · Mathematics 2020-09-02 Reza Jafarpour-Golzari

We prove the connectedness and calculate the diameter of the oriented graph of graftings associated to exotic complex projective structures on a compact surface S with a given holonomy representation of Fuchsian type. The oriented graph of…

Geometric Topology · Mathematics 2014-01-22 Gabriel Calsamiglia , Bertrand Deroin , Stefano Francaviglia

Chromatic polynomials have been studied extensively, giving us results such as the Fundamental Reduction Theorem and closed formulas for the chromatic polynomials of common classes of graphs. Though, none of those extend to the context of…

Combinatorics · Mathematics 2016-10-20 Pedro M. Recuero

In this paper, we present some properties on chromatic polynomials of hypergraphs which do not hold for chromatic polynomials of graphs. We first show that chromatic polynomials of hypergraphs have all integers as their zeros and contain…

Combinatorics · Mathematics 2017-04-24 Ruixue Zhang , Fengming Dong

The slope variety of a graph is an algebraic set whose points correspond to drawings of a graph. A complement-reducible graph (or cograph) is a graph without an induced four-vertex path. We construct a bijection between the zeroes of the…

Combinatorics · Mathematics 2010-10-13 Tom Enkosky

Let $G$ be a group. We define the coprime graph of subgroups of $G$, denoted by $\mathcal P(G)$, is a graph whose vertex set is the set of all proper subgroups of $G$, and two distinct vertices are adjacent if and only if the order of the…

Group Theory · Mathematics 2015-12-08 R. Rajkumar , P. Devi

A \emph{mixed graph} is a graph with directed edges, called arcs, and undirected edges. A $k$-coloring of the vertices is proper if colors from ${1,2,...,k}$ are assigned to each vertex such that $u$ and $v$ have different colors if $uv$ is…

Combinatorics · Mathematics 2016-05-10 Matthias Beck , Daniel Blado , Joseph Crawford , Taina Jean-Louis , Michael Young

There are many variations on partition functions for graph homomorphisms or colorings. The case considered here is a counting or hard constraint problem in which the range or color graph carries a free and vertex transitive Abelian group…

Combinatorics · Mathematics 2012-04-06 Eric Babson , Matthias Beck

Graph polynomials are polynomials assigned to graphs. Interestingly, they also arise in many areas outside graph theory as well. Many properties of graph polynomials have been widely studied. In this paper, we survey some results on the…

Combinatorics · Mathematics 2016-01-13 Xueliang Li , Yongtang Shi

A class $\mathcal{F}$ of graphs is $\chi$-bounded if there is a function $f$ such that $\chi(H)\le f(\omega(H))$ for all induced subgraphs $H$ of a graph in $\mathcal{F}$. If $f$ can be chosen to be a polynomial, we say that $\mathcal{F}$…

Combinatorics · Mathematics 2026-01-16 Maria Chudnovsky , Linda Cook , James Davies , Sang-il Oum
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