Results 51 to 60 of about 414,139 (194)
Approximation Algorithms for the Maximum Induced Planar and Outerplanar Subgraph Problems
Journal of Graph Algorithms and Applications, 2007 The task of finding the largest subset of vertices of a graph that induces a planar subgraph is known as the Maximum Induced Planar Subgraph problem (MIPS). In this paper, some new approximation algorithms for MIPS are introduced.
Kerri Morgan, Graham Farr
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The Minimal Nonplanar Strong Digraphs
Journal of Graph Theory, EarlyView.ABSTRACT Kuratowski's theorem says that the minimal (under subgraph containment) graphs that are not planar are the subdivisions of K 5 ${K}_{5}$ and of K 3 , 3 ${K}_{3,3}$. Here we study the minimal (under subdigraph containment) strongly‐connected digraphs that are not planar.
Stephen Bartell, Paul Seymour
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Straight-Line Drawings on Restricted Integer Grids in Two and Three Dimensions
Journal of Graph Algorithms and Applications, 2003 This paper investigates the following question: Given a grid ϕ, where ϕ is a proper subset of the integer 2D or 3D grid, which graphs admit straight-line crossing-free drawings with vertices located at (integral) grid points of ϕ?
Stefan Felsner +2 more
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Double domination in maximal outerplanar graphs
Open Mathematics, 2022 In graph GG, a vertex dominates itself and its neighbors. A subset S⊆V(G)S\subseteq V\left(G) is said to be a double-dominating set of GG if SS dominates every vertex of GG at least twice.
Zhuang Wei, Zheng Qiuju
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On the Threshold for Triangulations Inside Convex Polygons
Random Structures &Algorithms, Volume 69, Issue 2, September 2026.ABSTRACT Start with a large convex polygon and add all other edges inside independently with probability p$$ p $$. At what critical threshold pc$$ {p}_c $$ do triangulations of the polygon begin to appear? The first author and Gravner asked this question and observed that pc=Θ(1)$$ {p}_c=\Theta (1) $$, using the relationship with the Catalan numbers ...
Brett Kolesnik +2 more
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The subgraph isomorphism problem for outerplanar graphs [PDF]
, 1982 This paper deals with the subgraph isomorphism problem for outerplanar graphs (SUBOUTISOM). In general, since trees and forests are outerplanar, SUBOUTISOM is NP-complete.
SysŁ;o, Maciej M.
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Toric ideals of matching polytopes and edge colorings
Mathematika, Volume 72, Issue 2, April 2026.Abstract In this paper, we investigate the maximal degree of minimal generators of the toric ideal of the matching polytope of a graph. It is known that the toric ideal associated with a bipartite graph is generated by binomials of degree at most 3.
Kenta Mori +3 more
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On an interpolation property of outerplanar graphs
Discrete Applied Mathematics, 2006 Let \(D\) be an acyclic orientation of a graph \(G\). An arc of \(D\) is dependent if a directed cycle is created when it is reversed. Denote by \(d(D)\) the number of dependent arcs in \(D\). Let \(d_{\min}(G)\) be the minimum \(d(D)\), and \(d_{\max}(G)\) the maximum \(d(D)\), over all acyclic orientations \(D\) of \(G\).
Ko-Wei Lih, Chen-Ying Lin, Li-Da Tong
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L(2, 1)-Labelings of Some Families of Oriented Planar Graphs
Discussiones Mathematicae Graph Theory, 2014 In this paper we determine, or give lower and upper bounds on, the 2-dipath and oriented L(2, 1)-span of the family of planar graphs, planar graphs with girth 5, 11, 16, partial k-trees, outerplanar graphs and cacti.
Sen Sagnik
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On the spread of outerplanar graphs
Special Matrices, 2022 The spread of a graph is the difference between the largest and most negative eigenvalue of its adjacency matrix. We show that for sufficiently large nn, the nn-vertex outerplanar graph with maximum spread is a vertex joined to a linear forest with Ω(n ...
Gotshall Daniel +2 more
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