Results 21 to 30 of about 64,086 (307)
On clique-perfect and K-perfect graphs.
Ars Comb., 2006 80
Bonomo, Flavia +3 more
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On two consequences of Berge–Fulkerson conjecture
AKCE International Journal of Graphs and Combinatorics, 2020 The classical Berge–Fulkerson conjecture states that any bridgeless cubic graph admits a list of six perfect matchings such that each edge of belongs to two of the perfect matchings from the list.
Vahan V. Mkrtchyan, Gagik N. Vardanyan
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Two short proofs of the Perfect Forest Theorem
Theory and Applications of Graphs, 2017 A perfect forest is a spanning forest of a connected graph $G$, all of whose components are induced subgraphs of $G$ and such that all vertices have odd degree in the forest.
Yair Caro, Josef Lauri, Christina Zarb
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Triple Connected Domination Number of a Graph [PDF]
, 2012 The concept of triple connected graphs with real life application was introduced by considering the existence of a path containing any three vertices of a graph G.
Selvam Avadayappan +7 more
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A semi-strong perfect digraph theorem
AKCE International Journal of Graphs and Combinatorics, 2020 Reed (1987) showed that, if two graphs are P4-isomorphic, then either both are perfect or none of them is. In this note, we will derive an analogous result for perfect digraphs.
Stephan Dominique Andres +3 more
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Perfect Fuzzy Soft Tripartite Graphs and Their Complements
Discrete Dynamics in Nature and Society, 2022 Fuzzy soft graphs are efficient numerical tools for simulating the uncertainty of the real world. A fuzzy soft graph is a perfect fusion of the fuzzy soft set and the graph model that is widely used in a variety of fields.
Kalaichelvan Kalaiarasi +4 more
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Tight upper bound on the maximum anti-forcing numbers of graphs [PDF]
Discrete Mathematics & Theoretical Computer Science, 2017 Let $G$ be a simple graph with a perfect matching. Deng and Zhang showed that the maximum anti-forcing number of $G$ is no more than the cyclomatic number.
Lingjuan Shi, Heping Zhang
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Systems with the integer rounding property in normal monomial subrings
Anais da Academia Brasileira de Ciências, 2010 Let C be a clutter and let A be its incidence matrix. If the linear system x > 0; x A < 1 has the integer rounding property, we give a description of the canonical module and the a-invariant of certain normal subrings associated to C. If the clutter is a
Luis A. Dupont +2 more
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Extremal Values of Variable Sum Exdeg Index for Conjugated Bicyclic Graphs
Journal of Chemistry, 2021 A connected graph GV,E in which the number of edges is one more than its number of vertices is called a bicyclic graph. A perfect matching of a graph is a matching in which every vertex of the graph is incident to exactly one edge of the matching set ...
Muhammad Rizwan +3 more
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Discrete Applied Mathematics, 2019 Inspired by a famous characterization of perfect graphs due to Lovász, we define a graph $G$ to be sum-perfect if for every induced subgraph $H$ of $G$, $α(H) + ω(H) \geq |V(H)|$. (Here $α$ and $ω$ denote the stability number and clique number, respectively.) We give a set of $27$ graphs and we prove that a graph $G$ is sum-perfect if and only if $G ...
Bart Litjens +2 more
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