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相关论文: Degree powers in graphs with forbidden even cycle

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Yuster and Caro initiated the study of the sum of powers of the degrees of graphs with forbidden subgraphs. We settle two of their conjectures.

组合数学 · 数学 2007-05-23 Bela Bollobas , Vladimir Nikiforov

Erd\H{o}s and Gy\'arf\'as conjectured in 1994 that every graph with minimum degree at least 3 has a cycle of length a power of 2. In 2022, Gao and Shan (Graphs and Combinatorics) proved that the conjecture is true for $P_8$-free graphs,…

组合数学 · 数学 2025-02-12 Anand Shripad Hegde , R. B. Sandeep , P. Shashank

We study minimum degree conditions under which a graph $G$ contains $k$th powers of paths and cycles of arbitrary specified lengths. We determine precise thresholds, assuming that the order of $G$ is large. This extends a result of Allen,…

组合数学 · 数学 2023-06-05 Eng Keat Hng

We conjecture that a 2-connected graph $G$ of order $n$, in which $d(x)+d(y)\geq n-k$ for every pair of non-adjacent vertices $x$ and $y$, contains a cycle of length $n-k$ ($k<n/2$), unless $G$ is bipartite and $n-k$ is odd. This…

组合数学 · 数学 2011-11-10 Janusz Adamus

Let $G$ be a graph on $n$ vertices with degree sequence $(d_1,d_2......d_n)$. For a real $p \geq 1$, let $D_p(G)=\sum_{i=1}^nd_i^p$. A Tur\'an-type problem of degree power sum was initiated by Caro and Yuster \cite{caro2000degpower}:…

组合数学 · 数学 2024-04-11 Jiangdong Ai , Fankang He , Yihang Liu , Bo Ning

Given a positive integer $p$ and a graph $G$ with degree sequence $d_1,\dots,d_n$, we define $e_p(G)=\sum_{i=1}^n d_i^p$. Caro and Yuster introduced a Tur\'an-type problem for $e_p(G)$: Given a positive integer $p$ and a graph $H$,…

组合数学 · 数学 2018-01-09 Yongxin Lan , Henry Liu , Zhongmei Qin , Yongtang Shi

In this paper, we prove a tight minimum degree condition in general graphs for the existence of paths between two given endpoints, whose lengths form a long arithmetic progression with common difference one or two. This allows us to obtain…

组合数学 · 数学 2021-01-27 Jun Gao , Qingyi Huo , Chun-Hung Liu , Jie Ma

Given a graph $G$ with degree sequence $d_1,\dots, d_n$ and a positive integer $r$, let $e_r(G)=\sum_{i=1}^n d_i^r$. We denote by $\mathrm{ex}_r(n,F)$ the largest value of $e_r(G)$ among $n$-vertex $F$-free graphs $G$, and by…

组合数学 · 数学 2024-01-23 Dániel Gerbner

Let $G$ be a simple graph of order $n$ with degree sequence $(d_1,d_2,\cdots,d_n)$. For an integer $p>1$, let $e_p(G)=\sum_{i=1}^n d^{p}_i$ and let $ex_p(n,H)$ be the maximum value of $e_p(G)$ among all graphs with $n$ vertices that do not…

组合数学 · 数学 2023-12-13 Yufei Chang , Xiaodan Chen , Shuting Zhang

We prove a conjecture of Boros, Caro, F\"uredi and Yuster on the maximum number of edges in a 2-connected graph without repeated cycle lengths, which is a restricted version of a longstanding problem of Erd\H{o}s. Our proof together with…

组合数学 · 数学 2020-07-27 Jie Ma , Tianchi Yang

For a graph $G$ whose degree sequence is $d_{1},..., d_{n}$, and for a positive integer $p$, let $e_{p}(G)=\sum_{i=1}^{n}d_{i}^{p}$. For a fixed graph $H$, let $t_{p}(n,H)$ denote the maximum value of $e_{p}(G)$ taken over all graphs with…

组合数学 · 数学 2007-05-23 Y. Caro , R. Yuster

A graph is $P_8$-free if it contains no induced subgraph isomorphic to the path $P_8$ on eight vertices. In 1995, Erd\H{o}s and Gy\'{a}rf\'{a}s conjectured that every graph of minimum degree at least three contains a cycle whose length is a…

组合数学 · 数学 2021-09-06 Yuping Gao , Songling Shan

Let $P_{10}$ be a path on $10$ vertices. A graph is said to be $P_{10}$-free if it does not contain $P_{10}$ as an induced subgraph. The well-known Erd\H{o}s-Gy\'{a}rf\'{a}s Conjecture states that every graph with minimum degree at least…

组合数学 · 数学 2023-08-15 Zhiquan Hu , Changlong Shen

For a given finite graph $G$ of minimum degree at least $k$, let $G_{p}$ be a random subgraph of $G$ obtained by taking each edge independently with probability $p$. We prove that (i) if $p \ge \omega/k$ for a function $\omega=\omega(k)$…

组合数学 · 数学 2013-05-28 Michael Krivelevich , Choongbum Lee , Benny Sudakov

The P\'osa--Seymour conjecture determines the minimum degree threshold for forcing the $k$th power of a Hamilton cycle in a graph. After numerous partial results, Koml\'os, S\'ark\"ozy and Szemer\'edi proved the conjecture for sufficiently…

组合数学 · 数学 2025-10-01 Louis DeBiasio , Jie Han , Allan Lo , Theodore Molla , Simón Piga , Andrew Treglown

Let $G$ be a graph with degree sequence $d_1,d_2,\ldots,d_n$. Given a positive integer $p$, denote by $e_p(G)=\sum_{i=1}^n d_i^p$. Caro and Yuster introduced a Tur\'an-type problem for $e_p(G)$: given an integer $p$, how large can $e_p(G)$…

组合数学 · 数学 2013-05-15 Ran Gu , Xueliang Li , Yongtang Shi

We give an upper bound on the number of cycles in a simple graph in terms of its degree sequence, and apply this bound to resolve several conjectures of Kir\'aly and Arman and Tsaturian and to improve upper bounds on the maximum number of…

组合数学 · 数学 2019-07-30 Zdeněk Dvořák , Natasha Morrison , Jonathan A. Noel , Sergey Norin , Luke Postle

In 2022, Gao, Huo, Liu, and Ma proved that every graph with minimum degree at least $k+1$ contains $k$ admissible cycles, where a set of $k$ cycles is said to be admissible if their lengths form an arithmetic progression with common…

组合数学 · 数学 2026-04-03 Jifu Lin

We obtain sharp bounds for the number of n-cycles in a finite graph as a function of the number of edges, and prove that the complete graph is optimal in more ways than could be imagined. En route, we prove some sharp estimates on power…

组合数学 · 数学 2007-05-23 Igor Rivin

In a graph, $k$ cycles are {\em admissible} if their lengths form an arithmetic progression with common difference one or two. Let $G$ be a 2-connected graph with minimum degree at least $k\geqslant 4$. We prove that \begin{itemize} \item…

组合数学 · 数学 2025-11-06 Yandong Bai , Andrzej Grzesik , Binlong Li , Magdalena Prorok
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