Results 21 to 30 of about 4,003 (201)
On infinite outerplanar graphs [PDF]
In this Note, we study infinite graphs with locally finite outerplane embeddings, given a characterization by forbidden ...
Boza Prieto, Luis+2 more
openaire +4 more sources
Splitting Plane Graphs to Outerplanarity
Vertex splitting replaces a vertex by two copies and partitions its incident edges amongst the copies. This problem has been studied as a graph editing operation to achieve desired properties with as few splits as possible, most often planarity, for which the problem is NP-hard.Here we study how to minimize the number of splits to turn a plane graph ...
Gronemann, Martin+2 more
openaire +2 more sources
Irreducible nonmetrizable path systems in graphs
Abstract A path system P ${\mathscr{P}}$ in a graph G =(V , E ) $G=(V,E)$ is a collection of paths with a unique u v $uv$ path for every two vertices u , v ∈ V $u,v\in V$. We say that P ${\mathscr{P}}$ is consistent if for any path P ∈ P $P\in {\mathscr{P}}$, every subpath of P $P$ is also in P ${\mathscr{P}}$.
Daniel Cizma, Nati Linial
wiley +1 more source
Longest and shortest cycles in random planar graphs
Abstract Let be a graph chosen uniformly at random from the class of all planar graphs on vertex set with edges. We study the cycle and block structure of when . More precisely, we determine the asymptotic order of the length of the longest and shortest cycle in in the critical range when .
Mihyun Kang, Michael Missethan
wiley +1 more source
Approximation of pathwidth of outerplanar graphs [PDF]
Summary: There exists a polynomial time algorithm to compute the pathwidth of outerplanar graphs, but the large exponent makes this algorithm impractical. In this paper, we give an algorithm that, given a biconnected outerplanar graph \(G\), finds a path decomposition of \(G\) of pathwidth at most twice the pathwidth of \(G\) plus one.
Hans L. Bodlaender, Fedor V. Fomin
openaire +8 more sources
Site percolation and isoperimetric inequalities for plane graphs
We use isoperimetric inequalities combined with a new technique to prove upper bounds for the site percolation threshold of plane graphs with given minimum degree conditions. In the process we prove tight new isoperimetric bounds for certain classes of hyperbolic graphs.
John Haslegrave, Christoforos Panagiotis
wiley +1 more source
Large Induced Acyclic and Outerplanar Subgraphs of 2-Outerplanar Graph [PDF]
13 pages, 7 figures.
Glencora Borradaile+2 more
openalex +4 more sources
Strong Chromatic Index of Outerplanar Graphs
The strong chromatic index χs′(G) of a graph G is the minimum number of colors needed in a proper edge-coloring so that every color class induces a matching in G. It was proved In 2013, that every outerplanar graph G with Δ≥3 has χs′(G)≤3Δ−3.
Ying Wang+3 more
doaj +1 more source
An optimal labeling of a graph with $n$ vertices and $m$ edges is an injective assignment of the first $n$ nonnegative integers to the vertices, that induces, for each edge, a weight given by the sum of the labels of its end-vertices with the ...
Christian Barrientos, Maged Youssef
doaj +1 more source
Clique-Relaxed Graph Coloring [PDF]
We define a generalization of the chromatic number of a graph G called the k-clique-relaxed chromatic number, denoted χ(k)(G). We prove bounds on χ(k)(G) for all graphs G, including corollaries for outerplanar and planar graphs.
Dunn, Charles+5 more
core +2 more sources