Results 21 to 30 of about 771 (82)
Existence of Regular Nut Graphs for Degree at Most 11
Discussiones Mathematicae Graph Theory, 2020 A nut graph is a singular graph with one-dimensional kernel and corresponding eigenvector with no zero elements. The problem of determining the orders n for which d-regular nut graphs exist was recently posed by Gauci, Pisanski and Sciriha.
Fowler Patrick W. +4 more
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An upper bound of the basis number of the semi-strong product of bipartite graphs
SUT Journal of Mathematics, 2005 A basis of the cycle space, C(G), of a graph G is called a d-fold if each edge of G occurs in at most d cycles of the basis. The basis number, b(G), of a graph G is defined to be the least integer d such that G has a d-fold basis for its cycle space ...
M. Jaradat
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Characterizing Atoms that Result from Decomposition by Clique Separators
Discussiones Mathematicae Graph Theory, 2017 A graph is defined to be an atom if no minimal vertex separator induces a complete subgraph; thus, atoms are the graphs that are immune to clique separator decomposition.
McKee Terry A.
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On Some Properties of Antipodal Partial Cubes
Discussiones Mathematicae Graph Theory, 2020 We prove that an antipodal bipartite graph is a partial cube if and only it is interval monotone. Several characterizations of the principal cycles of an antipodal partial cube are given.
Polat Norbert
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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 ZAGREB INDICES AND ECCENTRIC CONNECTIVITY INDEX OF CERTAIN THORN GRAPHS
, 2016 The first three Zagreb indices of a graph G denoted, M1(G),M2(G) and M3(G), are well known. Equally well known is the eccentricity connectivity index denoted, ξ(G).
U. Mary +4 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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