Results 21 to 30 of about 730 (67)
Removable Edges on a Hamilton Cycle or Outside a Cycle in a 4-Connected Graph
Discussiones Mathematicae Graph Theory, 2021 Let G be a 4-connected graph. We call an edge e of G removable if the following sequence of operations results in a 4-connected graph: delete e from G; if there are vertices with degree 3 in G− e, then for each (of the at most two) such vertex x, delete ...
Wu Jichang +3 more
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On the Genus of the Co-Annihilating Graph of Commutative Rings
Discussiones Mathematicae - General Algebra and Applications, 2019 Let R be a commutative ring with identity and 𝒰R be the set of all nonzero non-units of R. The co-annihilating graph of R, denoted by 𝒞𝒜R, is a graph with vertex set 𝒰R and two vertices x and y are adjacent whenever ann(x) ∩ ann(y) = (0).
Selvakumar K., Karthik S.
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Some Observations on the Smallest Adjacency Eigenvalue of a Graph
Discussiones Mathematicae Graph Theory, 2020 In this paper, we discuss various connections between the smallest eigenvalue of the adjacency matrix of a graph and its structure. There are several techniques for obtaining upper bounds on the smallest eigenvalue, and some of them are based on Rayleigh
Cioabă Sebastian M. +2 more
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On the Genus of the Idempotent Graph of a Finite Commutative Ring
Discussiones Mathematicae - General Algebra and Applications, 2021 Let R be a finite commutative ring with identity. The idempotent graph of R is the simple undirected graph I(R) with vertex set, the set of all nontrivial idempotents of R and two distinct vertices x and y are adjacent if and only if xy = 0.
Belsi G. Gold, Kavitha S., Selvakumar K.
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Equimatchable Bipartite Graphs
Discussiones Mathematicae Graph Theory, 2023 A graph is called equimatchable if all of its maximal matchings have the same size. Lesk et al. [Equi-matchable graphs, Graph Theory and Combinatorics (Academic Press, London, 1984) 239–254] has provided a characterization of equimatchable bipartite ...
Büyükçolak Yasemin +2 more
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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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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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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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