Results 11 to 20 of about 875,640 (148)
Irreducible nonmetrizable path systems in graphs
Journal of Graph Theory, Volume 102, Issue 1, Page 5-14, January 2023., 2023 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
Random Structures &Algorithms, Volume 60, Issue 3, Page 462-505, May 2022., 2022 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
The Singularity of Oriented Outerplanar Graphs with a Given Number of Inner Edges
Journal of Mathematics, Volume 2022, Issue 1, 2022., 2022 A digraph is called oriented if there is at most one arc between two distinct vertices. An oriented graph is called nonsingular (singular) if its adjacency matrix A(D) is nonsingular (singular). In this paper, we study the singularity of the oriented outerplanar graph with a given number of inner edges.
Borui He +3 more
wiley +1 more source
Site percolation and isoperimetric inequalities for plane graphs
Random Structures &Algorithms, Volume 58, Issue 1, Page 150-163, January 2021., 2021 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
A Note on Edge‐Group Choosability of Planar Graphs without 5‐Cycles
Journal of Mathematics, Volume 2020, Issue 1, 2020., 2020 This paper is devoted to a study of the concept of edge‐group choosability of graphs. We say that G is edge‐k‐group choosable if its line graph is k‐group choosable. In this paper, we study an edge‐group choosability version of Vizing conjecture for planar graphs without 5‐cycles and for planar graphs without noninduced 5‐cycles (2010 Mathematics ...
Amir Khamseh, Andrei V. Kelarev
wiley +1 more source
Nonplanarity of Iterated Line Graphs
Journal of Mathematics, Volume 2020, Issue 1, 2020., 2020 The 1‐crossing index of a graph G is the smallest integer k such that the kth iterated line graph of G has crossing number greater than 1. In this paper, we show that the 1‐crossing index of a graph is either infinite or it is at most 5. Moreover, we give a full characterization of all graphs with respect to their 1‐crossing index.
Jing Wang, Alfred Peris
wiley +1 more source
Game Chromatic Number of Generalized Petersen Graphs and Jahangir Graphs
Journal of Applied Mathematics, Volume 2020, Issue 1, 2020., 2020 Let G = (V, E) be a graph, and two players Alice and Bob alternate turns coloring the vertices of the graph G a proper coloring where no two adjacent vertices are signed with the same color. Alice′s goal is to color the set of vertices using the minimum number of colors, which is called game chromatic number and is denoted by χg(G), while Bob′s goal is
Ramy Shaheen +3 more
wiley +1 more source
A Polynomial-time Algorithm for Outerplanar Diameter Improvement
, 2014 The Outerplanar Diameter Improvement problem asks, given a graph $G$ and an integer $D$, whether it is possible to add edges to $G$ in a way that the resulting graph is outerplanar and has diameter at most $D$.
Cohen, Nathann +6 more
core +3 more sources
Shortest Reconfiguration of Perfect Matchings via Alternating Cycles [PDF]
, 2019 Motivated by adjacency in perfect matching polytopes, we study the shortest reconfiguration problem of perfect matchings via alternating cycles. Namely, we want to find a shortest sequence of perfect matchings which transforms one given perfect matching ...
Ito, Takehiro +4 more
core +2 more sources
Face Sizes and the Connectivity of the Dual
Journal of Graph Theory, Volume 110, Issue 4, Page 379-391, December 2025.ABSTRACT For each c ≥ 1, we prove tight lower bounds on face sizes that must be present to allow 1‐ or 2‐cuts in simple duals of c‐connected maps. Using these bounds, we determine the smallest genus on which a c‐connected map can have a simple dual with a 2‐cut and give lower and some upper bounds for the smallest genus on which a c‐connected map can ...
Gunnar Brinkmann +2 more
wiley +1 more source