English
Related papers

Related papers: Stability for large forbidden subgraphs

200 papers

We extend the classical stability theorem of Erdos and Simonovits in two directions: first, we allow the order of the forbidden graph to grow as log of order of the host graph, and second, our extremal condition is on the spectral radius of…

Combinatorics · Mathematics 2007-11-26 Vladimir Nikiforov

The Erd\H{o}s-Simonovits stability theorem is one of the most widely used theorems in extremal graph theory. We obtain an Erd\H{o}s-Simonovits type stability theorem in multi-partite graphs. Different from the Erd\H{o}s-Simonovits stability…

Combinatorics · Mathematics 2026-01-14 Wanfang Chen , Changhong Lu , Long-Tu Yuan

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

Both the Simonovits stability theorem and the Nikiforov spectral stability theorem are powerful tools for solving exact values of Tur\'{a}n numbers in extremal graph theory. Recently, F\"{u}redi [J. Combin. Theory Ser. B 115 (2015)]…

Combinatorics · Mathematics 2022-03-08 Yongtao Li , Yuejian Peng

We prove a version of the strong Taylor's conjecture for stable graphs: if $G$ is a stable graph whose chromatic number is strictly greater than $\beth_2(\aleph_0)$ then $G$ contains all finite subgraphs of Sh$_n(\omega)$ and thus has…

Logic · Mathematics 2021-03-26 Yatir Halevi , Itay Kaplan , Saharon Shelah

The stability method is very useful for obtaining exact solutions of many extremal graph problems. Its key step is to establish the stability property which, roughly speaking, states that any two almost optimal graphs of the same order $n$…

Combinatorics · Mathematics 2010-07-30 Oleg Pikhurko

The classical stability theorem of Erd\H{o}s and Simonovits states that, for any fixed graph with chromatic number $k+1 \ge 3$, the following holds: every $n$-vertex graph that is $H$-free and has within $o(n^2)$ of the maximal possible…

Combinatorics · Mathematics 2018-10-05 Alexander Roberts , Alex Scott

We present a method which provides a unified framework for most stability theorems that have been proved in graph and hypergraph theory. Our main result reduces stability for a large class of hypergraph problems to the simpler question of…

Combinatorics · Mathematics 2022-11-15 Xizhi Liu , Dhruv Mubayi , Christian Reiher

Chudnovsky, Kim, Oum, and Seymour recently established that any prime graph contains one of a short list of induced prime subgraphs [1]. In the present paper we reprove their theorem using many of the same ideas, but with the key…

Logic · Mathematics 2015-11-10 M. Malliaris , C. Terry

We prove that if $G=(V,E)$ is an $\omega$-stable (respectively, superstable) graph with $\chi(G)>\aleph_0$ (respectively, $2^{\aleph_0}$) then $G$ contains all the finite subgraphs of the shift graph $\text{Sh}_n(\omega)$ for some $n$. We…

Logic · Mathematics 2021-03-23 Yatir Halevi , Itay Kaplan , Saharon Shelah

We establish a strong, geometric lower bound on the (sequential) topological complexity of the unordered configuration spaces of a general graph. As an application, we show that, for most graphs, the topological complexity eventually…

Algebraic Topology · Mathematics 2026-02-05 Ben Knudsen

The stability number of a forbidden family measures how many different structures are needed to approximate all near-extremal constructions avoiding it. An infinite stability number means that no finite list of structures suffices. We…

Combinatorics · Mathematics 2026-05-22 Heng Li , Xizhi Liu

In this paper we obtain the stability theorem for the independence number of $G(n, r, 1)$ graphs. This result was previously stated in the paper of M. Pyaderkin but the proof there was incorrect. We introduce the correct proof of the key…

Combinatorics · Mathematics 2025-10-22 M. Koshelev

In this thesis we consider ordered graphs (that is, graphs with a fixed linear ordering on their vertices). We summarize and further investigations on the number of edges an ordered graph may have while avoiding a fixed forbidden ordered…

Discrete Mathematics · Computer Science 2009-07-16 Craig Weidert

In this paper, we study the stability result of a well-known theorem of Bondy. We prove that for any 2-connected non-hamiltonian graph, if every vertex except for at most one vertex has degree at least $k$, then it contains a cycle of…

Combinatorics · Mathematics 2025-10-17 Bo Ning , Long-tu Yuan

Let G be a finite graph with the non-k-order property (essentially, a uniform finite bound on the size of an induced sub-half-graph). A major result of the paper applies model-theoretic arguments to obtain a stronger version of…

Logic · Mathematics 2015-08-20 M. Malliaris , S. Shelah

Consider the family of graphs without $ k $ node-disjoint odd cycles, where $ k $ is a constant. Determining the complexity of the stable set problem for such graphs $ G $ is a long-standing problem. We give a polynomial-time algorithm for…

Discrete Mathematics · Computer Science 2019-08-20 Michele Conforti , Samuel Fiorin , Tony Huynh , Gwenaël Joret , Stefan Weltge

The celebrated Erd\H{o}s-Hajnal conjecture says that any graph without a fixed induced subgraph $H$ contains a very large homogeneous set. A direct analog of this conjecture is not true for hypergraphs. In this paper we present two natural…

Combinatorics · Mathematics 2024-12-02 Fabian Arnold , Lior Gishboliner , Benny Sudakov

In this work, we establish an analogue result of the Erd\"os-Stone theorem of weighted digraphs using Regularity Lemma of digraphs. We give a stability result of oriented graphs and digraphs with forbidden blow-up transitive triangle and…

Combinatorics · Mathematics 2017-03-10 Jianxi Liu

Turan's theorem implies that every graph of order n with more edges than the r-partite Turan graph contains a complete graph of order r+1. We show that the same premise implies the existence of much larger graphs. We also prove…

Combinatorics · Mathematics 2007-11-22 Vladimir Nikiforov
‹ Prev 1 2 3 10 Next ›