Results 31 to 40 of about 771 (82)
On Some Characterizations of Antipodal Partial Cubes
Discussiones Mathematicae Graph Theory, 2019 We prove that any harmonic partial cube is antipodal, which was conjectured by Fukuda and K. Handa, Antipodal graphs and oriented matroids, Discrete Math. 111 (1993) 245–256.
Polat Norbert
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Describing Minor 5-Stars in 3-Polytopes with Minimum Degree 5 and No Vertices of Degree 6 or 7
Discussiones Mathematicae Graph Theory, 2022 In 1940, in attempts to solve the Four Color Problem, Henry Lebesgue gave an approximate description of the neighborhoods of 5-vertices in the class P5 of 3-polytopes with minimum degree 5. This description depends on 32 main parameters.
Batueva Ts.Ch-D. +3 more
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, 2012 The competition graph of a digraph $D$ is a (simple undirected) graph which has the same vertex set as $D$ and has an edge between two distinct vertices $x$ and $y$ if and only if there exists a vertex $v$ in $D$ such that $(x,v)$ and $(y,v)$ are arcs of
Boram Park +8 more
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Structural Properties of Recursively Partitionable Graphs with Connectivity 2
Discussiones Mathematicae Graph Theory, 2017 A connected graph G is said to be arbitrarily partitionable (AP for short) if for every partition (n1, . . . , np) of |V (G)| there exists a partition (V1, . . . , Vp) of V (G) such that each Vi induces a connected subgraph of G on ni vertices.
Baudon Olivier +3 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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The competition number of a graph and the dimension of its hole space
, 2011 The competition graph of a digraph D is a (simple undirected) graph which has the same vertex set as D and has an edge between x and y if and only if there exists a vertex v in D such that (x,v) and (y,v) are arcs of D.
Boram Park +16 more
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A Short Note on Undirected Fitch Graphs
, 2017 The symmetric version of Fitch's xenology relation coincides with class of complete multipartite graph and thus cannot convey any non-trivial phylogenetic ...
Geiß, Manuela +3 more
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Low 5-Stars at 5-Vertices in 3-Polytopes with Minimum Degree 5 and No Vertices of Degree from 7 to 9
Discussiones Mathematicae Graph Theory, 2020 In 1940, Lebesgue gave an approximate description of the neighborhoods of 5-vertices in the class P5 of 3-polytopes with minimum degree 5.
Borodin Oleg V. +2 more
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Journal of Mathematics, Volume 2025, Issue 1, 2025.In its crystalline state, the α‐icosahedral nanosheet of boron demonstrates superconductivity and thermal electronic properties. Mathematical research on a graph’s structure yields a graph descriptor, a numerical measure. Chemical graph theory employs connectivity descriptors to analyze molecular structures, providing crucial insights into many ...
Khalil Hadi Hakami +3 more
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Discussiones Mathematicae Graph Theory, 2018 A total-colored graph G is rainbow total-connected if any two vertices of G are connected by a path whose edges and internal vertices have distinct colors.
Sun Yuefang, Jin Zemin, Tu Jianhua
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