Results 21 to 30 of about 43 (43)
Connected even factors in k-tree
Open Mathematics, 2020 A connected even [2,2s]{[}2,2s]-factor of a graph G is a connected factor with all vertices of degree i(i=2,4,…,2s)i(i=2,4,\ldots ,2s), where s≥1s\ge 1 is an integer. In this paper, we show that a k+1s+2\tfrac{k+1}{s+2}-tough k-tree has a connected even [
Li Yinkui +4 more
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On the H-Force Number of Hamiltonian Graphs and Cycle Extendability
Discussiones Mathematicae Graph Theory, 2017 The H-force number h(G) of a hamiltonian graph G is the smallest cardinality of a set A ⊆ V (G) such that each cycle containing all vertices of A is hamiltonian. In this paper a lower and an upper bound of h(G) is given.
Hexel Erhard
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A sharp lower bound on the signless Laplacian index of graphs with (κ,τ)-regular sets
Special Matrices, 2018 A new lower bound on the largest eigenvalue of the signless Laplacian spectra for graphs with at least one (κ,τ)regular set is introduced and applied to the recognition of non-Hamiltonian graphs or graphs without a perfect matching.
Andeelić Milica +2 more
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Note on Ideal Based Zero-Divisor Graph of a Commutative Ring
Discussiones Mathematicae - General Algebra and Applications, 2017 In this paper, we consider the ideal based zero divisor graph ΓI(R) of a commutative ring R. We discuss some graph theoretical properties of ΓI(R) in relation with zero divisor graph.
Mallika A., Kala R., Selvakumar K.
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A Fan-Type Heavy Pair Of Subgraphs For Pancyclicity Of 2-Connected Graphs
Discussiones Mathematicae Graph Theory, 2016 Let G be a graph on n vertices and let H be a given graph. We say that G is pancyclic, if it contains cycles of all lengths from 3 up to n, and that it is H-f1-heavy, if for every induced subgraph K of G isomorphic to H and every two vertices u, v ∈ V (K)
Wideł Wojciech
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Uniquely hamiltonian graphs for many sets of degrees [PDF]
Discrete Mathematics & Theoretical Computer ScienceWe give constructive proofs for the existence of uniquely hamiltonian graphs for various sets of degrees. We give constructions for all sets with minimum 2 (a trivial case added for completeness), all sets with minimum 3 that contain an even number (for ...
Gunnar Brinkmann, Matthias De Pauw
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Hamiltonian Normal Cayley Graphs
Discussiones Mathematicae Graph Theory, 2019 A variant of the Lovász Conjecture on hamiltonian paths states that every finite connected Cayley graph contains a hamiltonian cycle. Given a finite group G and a connection set S, the Cayley graph Cay(G, S) will be called normal if for every g ∈ G we ...
Montellano-Ballesteros Juan José +1 more
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Alternating Hamiltonian cycles in $2$-edge-colored multigraphs [PDF]
Discrete Mathematics & Theoretical Computer Science, 2019 A path (cycle) in a $2$-edge-colored multigraph is alternating if no two consecutive edges have the same color. The problem of determining the existence of alternating Hamiltonian paths and cycles in $2$-edge-colored multigraphs is an $\mathcal{NP ...
Alejandro Contreras-Balbuena +2 more
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Edge-Connectivity and Edges of Even Factors of Graphs
Discussiones Mathematicae Graph Theory, 2019 An even factor of a graph is a spanning subgraph in which each vertex has a positive even degree. Jackson and Yoshimoto showed that if G is a 3-edge-connected graph with |G| ≥ 5 and v is a vertex with degree 3, then G has an even factor F containing two ...
Haghparast Nastaran, Kiani Dariush
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2-Connected Hamiltonian Claw-Free Graphs Involving Degree Sum of Adjacent Vertices
Discussiones Mathematicae Graph Theory, 2020 For a graph H, define σ¯2(H)=min{d(u)+d(v)|uv∈E(H)}{{\bar \sigma }_2} ( H ) = \min \left\{ {d ( u ) + d ( v )|uv \in E ( H )} \right\} . Let H be a 2-connected claw-free simple graph of order n with δ(H) ≥ 3. In [J. Graph Theory 86 (2017) 193–212], Chen
Tian Tao, Xiong Liming
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