Results 91 to 100 of about 4,003 (201)
On the Intersection Graphs Associeted to Posets
Discussiones Mathematicae - General Algebra and Applications, 2020 Let (P, ≤) be a poset with the least element 0. The intersection graph of ideals of P, denoted by G(P), is a graph whose vertices are all nontrivial ideals of P and two distinct vertices I and J are adjacent if and only if I ∩ J ≠ {0}.
Afkhami M. +2 more
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Reconstruction of maximal outerplanar graphs
Discrete Mathematics, 1972 AbstractS. Ulam has conjectured that every graph with three or more points is uniquely determined by its collection of point-deleted subgraphs. This has been proved for various classes of graphs, but progress has generally been confined to very symmetrical graphs and graphs with connectivity zero or one.
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A Survey of Maximal k-Degenerate Graphs and k-Trees
Theory and Applications of GraphsThis article surveys results on maximal $k$-degenerate graphs, $k$-trees, and related classes including simple $k$-trees, $k$-paths, maximal outerplanar graphs, and Apollonian networks.
Allan Bickle
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On Separating Path and Tree Systems in Graphs [PDF]
Discrete Mathematics & Theoretical Computer ScienceWe explore the concept of separating systems of vertex sets of graphs. A separating system of a set $X$ is a collection of subsets of $X$ such that for any pair of distinct elements in $X$, there exists a set in the separating system that contains ...
Ahmad Biniaz +8 more
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The Cayley Sum Graph of Ideals of a Lattice
Discussiones Mathematicae - General Algebra and Applications, 2020 Let L be a lattice, 𝒥(L) be the set of ideals of L and S be a subset of 𝒥 (L). In this paper, we introduce an undirected Cayley graph of L, denoted by ΓL,S with elements of 𝒥 (L) as the vertex set and, for two distinct vertices I and J, I is adjacent to ...
Afkhami Mojgan +2 more
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Small Superpatterns for Dominance Drawing
, 2013 We exploit the connection between dominance drawings of directed acyclic graphs and permutations, in both directions, to provide improved bounds on the size of universal point sets for certain types of dominance drawing and on superpatterns for certain ...
Bannister, Michael J. +2 more
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The role of twins in computing planar supports of hypergraphs
, 2020 A support or realization of a hypergraph $H$ is a graph $G$ on the same vertex as $H$ such that for each hyperedge of $H$ it holds that its vertices induce a connected subgraph of $G$.
Kanj, Iyad A. +4 more
core
To Prove Four Color Theorem [PDF]
, 2016 In this paper, we give a proof for four color theorem(four color conjecture). Our proof does not involve computer assistance and the most important is that it can be generalized to prove Hadwiger Conjecture. Moreover, we give algorithms to color and test
Cao, Weiwei, Yue, Weiya
core
Connected Graph Searching in Outerplanar Graphs
Electronic Notes in Discrete Mathematics, 2005 Search games are a powerfull tool for studying various connectivity parameters of graphs. In the classical search game, we consider an undirected graph G = (V, E) whose edges are initially contaminated. A set of searchers try to clean the graph. At the beginning the graph contains no searchers.
Ioan Todinca +2 more
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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. We show that the number of edges in random series-parallel graphs is asymptotically normal with linear mean and variance, and that the number of edges is ...
Manuel Bodirsky +3 more
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