Results 21 to 30 of about 1,769 (162)
Approximation of pathwidth of outerplanar graphs [PDF]
Journal of Algorithms, 2001 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
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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
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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
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
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On the Order Dimension of Outerplanar Maps [PDF]
Order, 2010 Schnyder characterized planar graphs in terms of order dimension. Brightwell and Trotter proved that the dimension of the vertex-edge-face poset $\Pvef{M}$ of a planar map $M$ is at most four. In this paper we investigate cases where $\dim(\Pvef{M}) \leq 3$ and also where $\dim(\Qvf{M}) \leq 3$; here $\Qvf{M}$ denotes the vertex-face poset of $M$.
Felsner, Stefan, Nilsson, Johan
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Genus Distributions of Cubic Outerplanar Graphs
Journal of Graph Algorithms and Applications, 2011 We present a quadratic-time algorithm for computing the genus distribution of any 3-regular outerplanar graph. Although recursions and some formulas for genus distributions have previously been calculated for bouquets and for various kinds of ladders ...
Jonathan Gross
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Structure and properties of maximal outerplanar graphs. [PDF]
, 2009 Outerplanar graphs are planar graphs that have a plane embedding in which each vertex lies on the boundary of the exterior region. An outerplanar graph is maximal outerplanar if the graph obtained by adding an edge is not outerplanar. Maximal outerplanar
Allgeier, Benjamin
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The Degree-Diameter Problem for Outerplanar Graphs
Discussiones Mathematicae Graph Theory, 2017 For positive integers Δ and D we define nΔ,D to be the largest number of vertices in an outerplanar graph of given maximum degree Δ and diameter D. We prove that nΔ,D=ΔD2+O (ΔD2−1)$n_{\Delta ,D} = \Delta ^{{D \over 2}} + O\left( {\Delta ^{{D \over 2 ...
Dankelmann Peter +2 more
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A note on zero-divisor graph of amalgamated duplication of a ring along an ideal
AKCE International Journal of Graphs and Combinatorics, 2017 Let be a commutative ring and be a non-zero ideal of . Let be the subring of consisting of the elements for and . In this paper we characterize all isomorphism classes of finite commutative rings with identity and ideal such that is planar.
A. Mallika, R. Kala
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A Characterization of Maximal Outerplanar-Open Distance Pattern Uniform Graphs
مجلة بغداد للعلوم, 2023 Let A ⊆ V(H) of any graph H, every node w of H be labeled using a set of numbers; , where d(w,v) denotes the distance between node w and the node v in H, known as its open A-distance pattern. A graph H is known as the open distance-pattern uniform (odpu)
BIBIN K JOSE
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