Results 71 to 80 of about 10,447 (245)
Some Properties of Regular Line Graphs
مجلة علوم ذي قار, 2019 In this paper, the concept of regular line graph has been introduced. The maximum number of vertices with different degrees in the regular line graphs has also been studied.
Akram Attar
doaj +4 more sources
Using random walks to generate associations between objects.
PLoS ONE, 2014 Measuring similarities between objects based on their attributes has been an important problem in many disciplines. Object-attribute associations can be depicted as links on a bipartite graph.
Muhammed A Yildirim, Michele Coscia
doaj +1 more source
Adaptive Bipartite Consensus of Second-Order Multi-Agent Systems With Bounded Disturbances
IEEE Access, 2020 This paper investigates distributed adaptive bipartite consensus for second-order multi-agent systems (MASs) with bounded disturbances under a signed graph. Based on adaptive variable structure control strategies, an adaptive bipartite consensus protocol
Haichuan Xu +3 more
doaj +1 more source
Journal of Graph Theory, EarlyView.ABSTRACT In an effort to understand the complexity of the maximum independent set problem, Chvátal introduced t‐perfect graphs. While a full characterization of this class remains open, important progress has been made for claw‐free graphs [Bruhn and Stein, Math. Program. 2012] and P 5 ${P}_{5}$‐free graphs [Bruhn and Fuchs, SIAM J. Discrete Math. 2017]
Yixin Cao, Shenghua Wang
wiley +1 more source
Tree Independence Number III. Thetas, Prisms and Stars
Journal of Graph Theory, EarlyView.ABSTRACT We prove that for every t ∈ N $t\in {\mathbb{N}}$ there exists τ = τ ( t ) ∈ N $\tau =\tau (t)\in {\mathbb{N}}$ such that every (theta, prism, K 1 , t ${K}_{1,t}$)‐free graph has tree independence number at most τ $\tau $ (where we allow “prisms” to have one path of length zero).
Maria Chudnovsky +2 more
wiley +1 more source
On Odd Covers of Cliques and Disjoint Unions
Journal of Graph Theory, EarlyView.ABSTRACT Babai and Frankl posed the “odd cover problem” of finding the minimum cardinality of a collection of complete bipartite graphs such that every edge of the complete graph of order n $n$ is covered an odd number of times. In a previous paper with O'Neill, some of the authors proved that this value is always ⌈ n / 2 ⌉ $\lceil n/2\rceil $ or ⌈ n /
Calum Buchanan +7 more
wiley +1 more source
Explicit 3‐colorings for Exponential Graphs
Journal of Graph Theory, EarlyView.ABSTRACT In 1985, El‐Zahar and Sauer showed that the chromatic number of the direct product of two 4‐chromatic graphs is 4, establishing a nontrivial case of Hedetniemi's conjecture, which has since been refuted in general. Their proof uses the concept of an exponential graph, showing that if a graph H $H$ has no proper 3‐coloring, then the exponential
Adrien Argento +2 more
wiley +1 more source
On balanced bipartitions of graphs [PDF]
AKCE International Journal of Graphs and Combinatorics, 2020 Bollobás and Scott conjectured that every graph G has a balanced bipartite spanning subgraph H such that for each for each In this paper, we consider the contrary side and show that every graphic sequence has a realization G which admits a balanced bipartite spanning subgraph H such that for each and we show that the bound is sharp.
openaire +2 more sources
One-Three Join: A Graph Operation and Its Consequences
Discussiones Mathematicae Graph Theory, 2017 In this paper, we introduce a graph operation, namely one-three join. We show that the graph G admits a one-three join if and only if either G is one of the basic graphs (bipartite, complement of bipartite, split graph) or G admits a constrained ...
Shalu M.A., Devi Yamini S.
doaj +1 more source
Saturated Partial Embeddings of Planar Graphs
Journal of Graph Theory, EarlyView.ABSTRACT In this work, we study how far one can deviate from optimal behavior when embedding a planar graph. For a planar graph G $G$, we say that a plane subgraph H ⊆ G $H\subseteq G$ is a plane‐saturated subgraph if adding any edge (possibly with new vertices) to H $H$ would either violate planarity or make the resulting graph no longer a subgraph of
Alexander Clifton, Nika Salia
wiley +1 more source