Results 31 to 40 of about 211 (163)
Directed Acyclic Outerplanar Graphs Have Constant Stack Number [PDF]
TheoretiCSThe stack number of a directed acyclic graph $G$ is the minimum $k$ for which there is a topological ordering of $G$ and a $k$-coloring of the edges such that no two edges of the same color cross, i.e., have alternating endpoints along the topological ...
Paul Jungeblut +2 more
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Adjacency posets of outerplanar graphs [PDF]
Discrete Mathematics, 2021 Felsner, Li and Trotter showed that the dimension of the adjacency poset of an outerplanar graph is at most 5, and gave an example of an outerplanar graph whose adjacency poset has dimension 4. We improve their upper bound to 4, which is then best possible.
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I/O-Optimal Algorithms for Outerplanar Graphs
Journal of Graph Algorithms and Applications, 2004 We present linear-I/O algorithms for fundamental graph problems on embedded outerplanar graphs. We show that breadth-first search, depth-first search, single-source shortest paths, triangulation, and computing an ϵ-separator of size O(1/ϵ) take O(scan(N))
Anil Maheshwari, Norbert Zeh
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On the number of series parallel and outerplanar graphs [PDF]
Discrete Mathematics & Theoretical Computer Science, 2005 We show that the number $g_n$ of labelled series-parallel graphs on $n$ vertices is asymptotically $g_n \sim g \cdot n^{-5/2} \gamma^n n!$, where $\gamma$ and $g$ are explicit computable constants.
Manuel Bodirsky +3 more
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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
Computing Minimum Cycle Bases in Weighted Partial 2-Trees in Linear Time
Journal of Graph Algorithms and Applications, 2014 We present a linear time algorithm for computing an implicit linear space representation of a minimum cycle basis in weighted partial 2-trees (i.e., graphs of treewidth at most two) with non-negative edge-weights. The implicit representation can be made
Carola Doerr +2 more
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Strong Chromatic Index of Outerplanar Graphs
Axioms, 2022 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
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Characterizations of outerplanar graphs
Discrete Mathematics, 1979 AbstractThe paper presents several characterizations of outerplanar graphs, some of them are counterparts of the well-known characterizations of planar graphs and the other provide very efficient tools for outerplanarity testing, coding (i.e. isomorphism testing), and counting such graphs.
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On the Edge-Length Ratio of Outerplanar Graphs [PDF]
Theoretical Computer Science, 2018 We show that any outerplanar graph admits a planar straightline drawing such that the length ratio of the longest to the shortest edges is strictly less than 2. This result is tight in the sense that for any $ε> 0$ there are outerplanar graphs that cannot be drawn with an edge-length ratio smaller than $2 - ε$.
Lazard, Sylvain +2 more
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