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Related papers: Csikv\'{a}ri's poset and Tutte polynomial

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T. K\'{a}lm\'{a}n (A version of Tutte's polynomial for hypergraphs, Adv. Math. 244 (2013) 823-873.) introduced the interior and exterior polynomials which are generalizations of the Tutte polynomial $T(x,y)$ on plane points $(1/x,1)$ and…

Combinatorics · Mathematics 2022-02-01 Xiaxia Guan , Xian'an Jin , Tianlong Ma

We consider 3 (weighted) posets associated with a graph G - the poset P(G) of distinct induced unlabelled subgraphs, the lattice Omega(G) of distinct unlabelled graphs induced by connected partitions, and the poset Q(G) of distinct…

Combinatorics · Mathematics 2015-08-19 Bhalchandra D. Thatte

In a recent paper, we studied the interaction between the automorphism group of a graph and its Tutte polynomial. More precisely, we proved that certain symmetries of graphs are clearly reflected by their Tutte polynomials. The purpose of…

Combinatorics · Mathematics 2018-02-26 Chbili Nafaa

Chv\'atal showed that for any tree $T$ with $k$ edges the Ramsey number $R(T,n)=k(n-1)+1$ ("Tree-complete graph Ramsey numbers." Journal of Graph Theory 1.1 (1977): 93-93). For $r=3$ or $4$, we show that, if $T$ is an $r$-uniform…

Combinatorics · Mathematics 2024-12-30 Jiaxi Nie

The following sharpening of Tur\'an's theorem is proved. Let $T_{n,p}$ denote the complete $p$--partite graph of order $n$ having the maximum number of edges. If $G$ is an $n$-vertex $K_{p+1}$-free graph with $e(T_{n,p})-t$ edges then there…

Combinatorics · Mathematics 2015-01-14 Zoltán Füredi

We prove some variants of the exponential formula and apply them to the multivariate Tutte polynomials (also known as Potts-model partition functions) of graphs. We also prove some further identities for the multivariate Tutte polynomial,…

Combinatorics · Mathematics 2009-11-16 Alexander D. Scott , Alan D. Sokal

We investigate structural properties of the cone of roots of relative Steiner polynomials of convex bodies. We prove that they are closed, monotonous with respect to the dimension, and that they cover the whole upper half-plane, except the…

Metric Geometry · Mathematics 2011-12-21 Martin Henk , María A. Hernández Cifre , Eugenia Saorín

We establish maximal trees and graphs for the difference of average distance and proximity proving thus the corresponding conjecture posed in [4]. We also establish maximal trees for the difference of average eccentricity and remoteness and…

Combinatorics · Mathematics 2020-10-22 Jelena Sedlar

Recently Csikv\'ari \cite{csik} proved a conjecture of Nikiforov concerning the number of closed walks on trees. Our aim is to extend his theorem to all walks. In addition, we give a simpler proof of Csikv\'ari's result and answer one of…

Combinatorics · Mathematics 2010-02-16 Bela Bollobas , Mykhaylo Tyomkyn

Loebl, Komlos, and Sos conjectured that if at least half of the vertices of a graph G have degree at least some natural number k, then every tree with at most k edges is a subgraph of G. Our main result is an approximate version of this…

Combinatorics · Mathematics 2011-05-10 Diana Piguet , Maya Jakobine Stein

For a graph $G$, we write $G\rightarrow \big(K_{r+1},\mathcal{T}(n,D)\big)$ if every blue-red colouring of the edges of $G$ contains either a blue copy of $K_{r+1}$, or a red copy of each tree with $n$ edges and maximum degree at most $D$.…

Combinatorics · Mathematics 2021-04-06 Pedro Araújo , Luiz Moreira , Matías Pavez-Signé

The coefficients of the chain polynomial of a finite poset enumerate chains in the poset by their number of elements. It has been a challenging open problem to determine which posets have real-rooted chain polynomials. Two new classes of…

Combinatorics · Mathematics 2025-12-02 Christos A. Athanasiadis , Theo Douvropoulos , Katerina Kalampogia-Evangelinou

In this survey of graph polynomials, we emphasize the Tutte polynomial and a selection of closely related graph polynomials. We explore some of the Tutte polynomial's many properties and applications and we use the Tutte polynomial to…

Combinatorics · Mathematics 2008-06-28 Joanna Ellis-Monaghan , Criel Merino

Packing graphs is a combinatorial problem where several given graphs are being mapped into a common host graph such that every edge is used at most once. In the planar tree packing problem we are given two trees T1 and T2 on n vertices and…

Computational Geometry · Computer Science 2016-03-28 Markus Geyer , Michael Hoffmann , Michael Kaufmann , Vincent Kusters , Csaba D. Tóth

The Graceful Tree Conjecture of Rosa from 1967 asserts that the vertices of each tree T of order n can be injectively labelled by using the numbers {1,2,...,n} in such a way that the absolute differences induced on the edges are pairwise…

Combinatorics · Mathematics 2020-06-23 Anna Adamaszek , Peter Allen , Codrut Grosu , Jan Hladky

We give a fine-grained classification of evaluating the Tutte polynomial $T(G;x,y)$ on all integer points on graphs with small treewidth and cutwidth. Specifically, we show for any point $(x,y) \in \mathbb{Z}^2$ that either - can be…

Computational Complexity · Computer Science 2023-07-04 Isja Mannens , Jesper Nederlof

The Tutte polynomial is an important invariant of graphs and matroids. Chen and Guo \emph{[Adv. in Appl. Math. 166 (2025) 102868.]} proved that for a $(k+1)$-edge connected graph $G$ and for any $i$ with $0\leq i <\frac{3(k+1)}{2}$,…

Combinatorics · Mathematics 2025-09-29 Xiaxia Guan , Xian'an Jin , Tianlong Ma , Weihua Yang

The Gy\'arf\'as tree packing conjecture asserts that any set of trees with $2,3, ..., k$ vertices has an (edge-disjoint) packing into the complete graph on $k$ vertices. Gy\'arf\'as and Lehel proved that the conjecture holds in some special…

Combinatorics · Mathematics 2011-10-24 Dániel Gerbner , Balázs Keszegh , Cory Palmer

We prove that an infinite family of semiprimitive groups are graph-restrictive. This adds to the evidence for the validity of the PSV Conjecture and increases the minimal imprimitive degree for which this conjecture is open to 12. Our…

Group Theory · Mathematics 2015-01-19 Michael Giudici , Luke Morgan

Starting from the data of an arbor, which is a rooted tree with vertices decorated by disjoint sets, we introduce a lattice polytope and a partial order on its lattice points. We give recursive algorithms for various classical invariants of…

Combinatorics · Mathematics 2025-08-26 Frédéric Chapoton