Results 21 to 30 of about 414,139 (194)
Planar L-Drawings of Bimodal Graphs
Journal of Graph Algorithms and Applications, 2022 In a planar L-drawing of a directed graph (digraph) each edge $e$ is represented as a polyline composed of a vertical segment starting at the tail of $e$ and a horizontal segment ending at the head of $e$. Distinct edges may overlap, but not cross.
Patrizio Angelini +3 more
doaj +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 generalization of outerplanar graphs [PDF]
Časopis pro pěstování matematiky, 1988 A planar graph is said to be a generalized outerplanar graph if it has an embedding in the plane in which every edge is incident to a vertex laying on the boundary of the outer face. The author presents a characterization of generalized outerplanar graphs by means of a set of exactly 12 forbidden subgraphs (up to homeomorphism).
openaire +1 more source
Planar, Outerplanar, and Toroidal Graphs of the Generalized Zero‐Divisor Graph of Commutative Rings
Journal of Mathematics, Volume 2021, Issue 1, 2021., 2021 Let A be a commutative ring with unity and let set of all zero divisors of A be denoted by ZA. An ideal ℐ of the ring A is said to be essential if it has a nonzero intersection with every nonzero ideal of A. It is denoted by ℐ≤eA. The generalized zero‐divisor graph denoted by ΓgA is an undirected graph with vertex set ZA∗ (set of all nonzero zero ...
Abdulaziz M. Alanazi +3 more
wiley +1 more source
Minimum Cycle Base of Graphs Identified by Two Planar Graphs [PDF]
, 2007 In this paper, we study the minimum cycle base of the planar graphs obtained from two 2-connected planar graphs by identifying an edge (or a cycle) of one graph with the corresponding edge (or cycle) of another, related with map geometries, i.e ...
Han, Ren, Dengju, Ma
core +1 more source
Free Choosability of Outerplanar Graphs [PDF]
Graphs and Combinatorics, 2015 zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Aubry, Yves +2 more
openaire +3 more sources
Straight-Line Grid Drawings of Label-Constrained Outerplanar Graphs with O(n log n) Area
Journal of Graph Algorithms and Applications, 2011 A straight-line grid drawing of a planar graph G is a drawing of G on an integer grid such that each vertex is drawn as a grid point and each edge is drawn as a straight-line segment without edge crossings.
Md. Rezaul Karim +2 more
doaj +1 more source
A generalization of outerplanar graphs
Discrete Mathematics, 1984 A graph G is said to be W-outerplanar if it can be embedded in the plane so that all vertices of a given set \(W\subset V(G)\) lie on the boundary of one face. A characterization of such graphs is given by means of forbidden subgraphs, and an algorithm for W-outerplanarity testing is described. The results overlap, in part, with those of \textit{V.
Lía Oubiña, R. Zucchello
openaire +3 more sources