English
Related papers

Related papers: Edge Disjoint Caterpillar Realizations

200 papers

Let $m\ge 1$ be an integer and $G$ be a graph with $m$ edges. We say that $G$ has an antimagic orientation if $G$ has an orientation $D$ and a bijection $\tau:A(D)\rightarrow \{1,2,\ldots,m\}$ such that no two vertices in $D$ have the same…

Combinatorics · Mathematics 2021-06-22 Jessica Ferraro , Genevieve Newkirk , Songling Shan

A rainbow spanning tree in an edge-colored graph is a spanning tree in which each edge is a different color. Carraher, Hartke, and Horn showed that for $n$ and $C$ large enough, if $G$ is an edge-colored copy of $K_n$ in which each color…

Combinatorics · Mathematics 2017-04-04 Paul Horn , Lauren M. Nelsen

A graph $G=(V,E)$ with a vertex set $V$ and an edge set $E$ is called a pairwise compatibility graph (PCG, for short) if there are a tree $T$ whose leaf set is $V$, a non-negative edge weight $w$ in $T$, and two non-negative reals…

Data Structures and Algorithms · Computer Science 2020-07-23 Mingyu Xiao , Hiroshi Nagamochi

The girth of a graph $G$ is the length of a shortest cycle of $G$. Jiang (JCT-B, 2001) showed that every graph $G$ with girth at least $2\ell+1$ and minimum degree at least $k/\ell$ contains every tree $T$ with $k$ edges whose maximum…

Combinatorics · Mathematics 2025-09-23 Junying Lu , Yaojun Chen

Let $G$ be a nontrivial graph with minimum degree $\delta$ and $k$ an integer with $k\ge 2$. In the literature, there are eigenvalue conditions that imply $G$ contains $k$ edge-disjoint spanning trees. We give eigenvalue conditions that…

Combinatorics · Mathematics 2025-04-02 Jin Cai , Bo Zhou

A simple graph is called triangular if every edge of it belongs to a triangle. We conjecture that any graphical degree sequence all terms of which are greater than or equal to 4 has a triangular realisation, and establish this conjecture…

Combinatorics · Mathematics 2023-04-03 Benjamin Egan , Yuri Nikolayevsky

Multi-edge trees as introduced in a recent paper of Dziemia\'nczuk are plane trees where multiple edges are allowed. We first show that $d$-ary multi-edge trees where the out-degrees are bounded by $d$ are in bijection with classical…

Combinatorics · Mathematics 2016-05-18 Clemens Heuberger , Helmut Prodinger , Stephan Wagner

Bermond and Thomassen conjectured that every digraph with minimum outdegree at least $2k-1$ contains $k$ vertex disjoint cycles. So far the conjecture was verified for $k\le 3$. Here we generalise the question asking for all outdegree…

Combinatorics · Mathematics 2022-08-18 Mikołaj Lewandowski , Joanna Polcyn , Christian Reiher

In this paper, we show that every $O(m)$-edge-connected simple graph $G$ of size divisible by $m$ with minimum degree at least $2^{O(m)}$ has an edge-decomposition into isomorphic copies of any given tree $T$ of size $m$. Moreover, the…

Combinatorics · Mathematics 2024-09-04 Morteza Hasanvand

It is conjectured that every edge-colored complete graph $G$ on $n$ vertices satisfying $\Delta^{mon}(G)\leq n-3k+1$ contains $k$ vertex-disjoint properly edge-colored cycles. We confirm this conjecture for $k=2$, prove several additional…

Combinatorics · Mathematics 2017-08-30 Ruonan Li , Hajo Broersma , Shenggui Zhang

Given a bipartite graph $G=(V_b,V_r,E)$, the $2$-Level Quasi-Planarity problem asks for the existence of a drawing of $G$ in the plane such that the vertices in $V_b$ and in $V_r$ lie along two parallel lines $\ell_b$ and $\ell_r$,…

Data Structures and Algorithms · Computer Science 2020-11-05 Patrizio Angelini , Giordano Da Lozzo , Giuseppe Di Battista , Fabrizio Frati , Maurizio Patrignani

We provide the necessary and sufficient conditions for the edge-binomials of the tree forming a $d$-sequence in terms of the degree sequence notion of a graph. We study the regularity of powers of the binomial edge ideals of trees generated…

Commutative Algebra · Mathematics 2023-05-19 Marie Amalore Nambi , Neeraj Kumar

We study noncrossing geometric graphs and their disjoint compatible geometric matchings. Given a cycle (a polygon) P we want to draw a set of pairwise disjoint straight-line edges with endpoints on the vertices of P such that these new…

Combinatorics · Mathematics 2020-08-20 Alexander Pilz , Jonathan Rollin , Lena Schlipf , André Schulz

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

We study upward planar straight-line embeddings (UPSE) of directed trees on given point sets. The given point set $S$ has size at least the number of vertices in the tree. For the special case where the tree is a path $P$ we show that: (a)…

Computational Geometry · Computer Science 2020-12-22 Elena Arseneva , Pilar Cano , Linda Kleist , Tamara Mchedlidze , Saeed Mehrabi , Irene Parada , Pavel Valtr

In this paper, we refer to a asymptotic degree sequence as $\mathscr{D}=(d_1,d_2,\dots,d_n)$. The examination of topological indices on trees gives us a general overview through bounds to find the maximum and minimum bounds which reflect…

Combinatorics · Mathematics 2025-12-16 Jasem Hamoud , Duaa Abdullah

This paper addresses the following questions for a given tree $T$ and integer $d\geq2$: (1) What is the minimum number of degree-$d$ subtrees that partition $E(T)$? (2) What is the minimum number of degree-$d$ subtrees that cover $E(T)$? We…

Combinatorics · Mathematics 2010-08-20 David R. Wood

Loebl, Komlos, and Sos conjectured that if at least half the vertices of a graph G have degree at least some k, then every tree with at most k edges is a subgraph of G. We prove the conjecture for all trees of diameter at most 5 and for a…

Combinatorics · Mathematics 2007-12-21 Diana Piguet , Maya Jakobine Stein

A geometric graph is a graph drawn in the plane so that its vertices and edges are represented by points in general position and straight line segments, respectively. A vertex of a geometric graph is called pointed if it lies outside of the…

Combinatorics · Mathematics 2022-08-31 Nikita Chernega , Alexandr Polyanskii , Rinat Sadykov

A topological graph drawn on a cylinder whose base is horizontal is \emph{angularly monotone} if every vertical line intersects every edge at most once. Let $c(n)$ denote the maximum number $c$ such that every simple angularly monotone…

Combinatorics · Mathematics 2013-07-17 Radoslav Fulek