English
Related papers

Related papers: Long induced paths in $K_{s, s}$-free graphs

200 papers

Let us say a graph is $s\mathcal{O}$-free, where $s\ge 1$ is an integer, if there do not exist $s$ cycles of the graph that are pairwise vertex-disjoint and have no edges joining them. The structure of such graphs, even when $s=2$, is not…

Combinatorics · Mathematics 2023-01-11 Tung Nguyen , Alex Scott , Paul Seymour

Consider a graph $G$ with a path $P$ of order $n$. What conditions force $G$ to also have a long induced path? As complete bipartite graphs have long paths but no long induced paths, a natural restriction is to forbid some fixed complete…

Combinatorics · Mathematics 2024-11-14 Julien Duron , Louis Esperet , Jean-Florent Raymond

We prove that every 3-connected planar graph on $n$ vertices contains an induced path on $\Omega(\log n)$ vertices, which is best possible and improves the best known lower bound by a multiplicative factor of $\log \log n$. We deduce that…

Combinatorics · Mathematics 2016-12-20 Louis Esperet , Laetitia Lemoine , Frédéric Maffray

In this paper we show that every graph of pathwidth less than $k$ that has a path of order $n$ also has an induced path of order at least $\frac{1}{3} n^{1/k}$. This is an exponential improvement and a generalization of the polylogarithmic…

Discrete Mathematics · Computer Science 2023-01-04 Claire Hilaire , Jean-Florent Raymond

An induced path factor of a graph $G$ is a set of induced paths in $G$ with the property that every vertex of $G$ is in exactly one of the paths. The induced path number $\rho(G)$ of $G$ is the minimum number of paths in an induced path…

Combinatorics · Mathematics 2021-04-19 Saieed Akbari , Daniel Horsley , Ian M. Wanless

In any graph, the maximum size of an induced path is bounded by the maximum size of a path. However, in the general case, one cannot find a converse bound, even up to an arbitrary function, as evidenced by the case of cliques. Galvin, Rival…

Combinatorics · Mathematics 2025-09-23 Julien Duron , Hugo Jacob

In 2012, Ne\v{s}et\v{r}il and Ossona de Mendez proved that graphs of bounded degeneracy that have a path of order $n$ also have an induced path of order $\Omega(\log \log n)$. In this paper we give an almost matching upper bound by…

Combinatorics · Mathematics 2026-02-13 Basile Couëtoux , Oscar Defrain , Jean-Florent Raymond

The altitude of a graph $G$, denoted $f(G)$, is the largest integer $k$ such that under each ordering of $E(G)$, there exists a path of length $k$ which traverses edges in increasing order. In 1971, Chv\'atal and Koml\'os asked for…

Combinatorics · Mathematics 2015-09-08 Kevin G. Milans

We show that for $d\ge d_0(\epsilon)$, with high probability, the random graph $G(n,d/n)$ contains an induced path of length $(3/2-\epsilon)\frac{n}{d}\log d$. This improves a result obtained independently by Luczak and Suen in the early…

Combinatorics · Mathematics 2021-02-19 Stefan Glock

An extension of an induced path $P$ in a graph $G$ is an induced path $P'$ such that deleting the endpoints of $P'$ results in $P$. An induced path in a graph is said to be avoidable if each of its extensions is contained in an induced…

Combinatorics · Mathematics 2021-10-22 Vladimir Gurvich , Matjaž Krnc , Martin Milanič , Mikhail Vyalyi

Graphs of bounded degeneracy are known to contain induced paths of order $\Omega(\log \log n)$ when they contain a path of order $n$, as proved by Ne\v{s}et\v{r}il and Ossona de Mendez (2012). In 2016 Esperet, Lemoine, and Maffray…

Combinatorics · Mathematics 2023-12-21 Oscar Defrain , Jean-Florent Raymond

Given a triangle-free graph $G$ with chromatic number $k$ and a proper vertex coloring $\phi$ of $G$, it is conjectured that $G$ contains an induced rainbow path on $k$ vertices under $\phi$. Scott and Seymour proved the existence of an…

Combinatorics · Mathematics 2026-01-05 N. R. Aravind , Shiwali Gupta , Rogers Mathew

We prove that any bounded degree regular graph with sufficiently strong spectral expansion contains an induced path of linear length. This is the first such result for expanders, strengthening an analogous result in the random setting by…

Combinatorics · Mathematics 2025-03-05 Nemanja Draganić , Peter Keevash

We prove that every connected triangle-free graph on $n$ vertices contains an induced tree on $\exp(c\sqrt{\log n})$ vertices, where $c$ is a positive constant. The best known upper bound is $(2+o(1))\sqrt n$. This partially answers…

Combinatorics · Mathematics 2007-12-03 Jiri Matousek , Robert Samal

Consider a graph $G$ with a long path $P$. When is it the case that $G$ also contains a long induced path? This question has been investigated in general as well as within a number of different graph classes since the 80s. We have recently…

Discrete Mathematics · Computer Science 2026-01-22 Julien Duron , Louis Esperet , Jean-Florent Raymond

We present a modification of the Depth first search algorithm, suited for finding long induced paths. We use it to give simple proofs of the following results. We show that the induced size-Ramsey number of paths satisfies…

Combinatorics · Mathematics 2022-03-02 Nemanja Draganić , Stefan Glock , Michael Krivelevich

Paths P1,...,Pk in a graph G=(V,E) are said to be mutually induced if for any 1 <= i < j <= k, Pi and Pj have neither common vertices nor adjacent vertices (except perhaps their end-vertices). The Induced Disjoint Paths problem is to test…

Discrete Mathematics · Computer Science 2014-03-07 Petr A. Golovach , Daniel Paulusma , Erik Jan van Leeuwen

Let $G$ be an infinite graph whose vertex set is the set of positive integers, and let $G_n$ be the subgraph of $G$ induced by the vertices $\{1,2, \dots , n \}$. An increasing path of length $k$ in $G$, denoted $I_k$, is a sequence of…

Combinatorics · Mathematics 2015-12-22 Xing Peng , Craig Timmons

For a real c \geq 1 and an integer n, let f(n,c) denote the maximum integer f so that every graph on n vertices contains an induced subgraph on at least f vertices in which the maximum degree is at most c times the minimum degree. Thus, in…

Combinatorics · Mathematics 2008-02-25 Noga Alon , Michael Krivelevich , Benny Sudakov

We show that every complete $n$-vertex simple topological graph contains a topological subgraph on at least $(\log n)^{1/4 - o(1)}$ vertices that is weakly isomorphic to the complete convex geometric graph or the complete twisted graph.…

Combinatorics · Mathematics 2022-09-08 Andrew Suk , Ji Zeng
‹ Prev 1 2 3 10 Next ›