Results 31 to 40 of about 96,525 (309)
Journal of Combinatorial Theory, Series B, 1997 A covering projection from a graph \(G\) onto a graph \(H\) is a ``local isomorphism'': a mapping from the vertex set of \(G\) onto the vertex set of \(H\) such that, for every \(v\in V(G)\), the neighborhood of \(v\) is mapped bijectively onto the neighborhood (in \(H\)) of the image of \(v\).
Jan Kratochvíl +2 more
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On single-valued co-neutrosophic graphs [PDF]
Neutrosophic Sets and Systems, 2018 In this paper, we introduce the notion of a single-valued co-neutrosophic graphs and study some methods of construction of new single-valued co-neutrosophic graphs.
R. Dhavaseelan +3 more
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On Automorphisms of a Distance-Regular Graph with Intersection Array {125,96,1;1,48,125} [PDF]
Учёные записки Казанского университета: Серия Физико-математические науки, 2017 J. Koolen posed the problem of studying distance-regular graphs in which neighborhoods of vertices are strongly regular graphs with the second eigenvalue ≤ t for the given positive integer t.
V.V. Bitkina, A.A. Makhnev
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New concepts of regular and (highly) irregular vague graphs with applications
Fuzzy Information and Engineering, 2017 In this paper, some types of vague graphs are introdaced such as dm-regular, tdm-regular, m-highly irregular and m-highly totally irregular vague graphs are introduced and some properties of them are discussed.
Elham Darabian +3 more
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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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On pseudo regular spherical fuzzy graphs
Ratio Mathematica, 2023 In this paper, pseudo regular and totally pseudo regular spherical fuzzy graphs are defined using pseudo degree and total pseudo degree of a vertex. A necessary and sufficient condition for pseudo regular spherical fuzzy graph is given.
B Mohamed Harif, A Nazeera Begam
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Journal of Combinatorial Theory, Series B, 1971 AbstractThis paper is a continuation of [1] and we shall use the same terminology. The main result of this part is the following: Suppose that the automorphism group of a connected graph of valency p + 1, p a prime, has a subgroup which acts as a regular permutation group on the set of s-arcs of the graph. Then s ≤ 7 and s ≠ 6.
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On orbital regular graphs and frobenius graphs
Discrete Mathematics, 1998 A group is a Frobenius group if it acts transitively but not freely on a set such that no two elements are fixed by a non-trivial element of the group. An orbital-regular graph is a finite graph whose automorphism group has a subgroup which is transitive on the edges and contains no element which fixes two vertices.
Xin Gui Fang +2 more
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Regular star complements in strongly regular graphs [PDF]
, 2012 We prove that, aside from the complete multipartite graphs and graphs of Steiner type, there are only finitely many connected strongly regular graphs with a regular star complement of prescribed degree s∈N.
Peter Rowlinson, Rowlinson, Peter
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Quasi-randomness and algorithmic regularity for graphs with general degree distributions [PDF]
, 2010 We deal with two intimately related subjects: quasi-randomness and regular partitions. The purpose of the concept of quasi-randomness is to express how much a given graph “resembles” a random one.
Schacht, Mathias +5 more
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