Results 11 to 20 of about 59,692 (266)
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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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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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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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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Commuting decomposition of Kn1,n2,...,nk through realization of the product A(G)A(GPk )
Special Matrices, 2018 In this paper, we introduce the notion of perfect matching property for a k-partition of vertex set of given graph. We consider nontrivial graphs G and GPk , the k-complement of graph G with respect to a kpartition of V(G), to prove that A(G)A(GPk ) is ...
Bhat K. Arathi, Sudhakara G.
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Random Structures & Algorithms, 2018 We investigate the asymptotic structure of a random perfect graph Pn sampled uniformly from the set of perfect graphs on vertex set . Our approach is based on the result of Prömel and Steger that almost all perfect graphs are generalised split graphs, together with a method to generate such graphs almost uniformly.
McDiarmid, C, Yolov, N
openaire +2 more sources
On kernels in strongly game-perfect digraphs and a characterisation of weakly game-perfect digraphs
AKCE International Journal of Graphs and Combinatorics, 2020 We prove that the game-perfect digraphs defined by Andres (2012) with regard to a digraph version of the maker-breaker graph colouring game introduced by Bodlaender (1991) always have a kernel.
Stephan Dominique Andres
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On the number of perfect matchings in random polygonal chains
Open Mathematics, 2023 Let GG be a graph. A perfect matching of GG is a regular spanning subgraph of degree one. Enumeration of perfect matchings of a (molecule) graph is interest in chemistry, physics, and mathematics.
Wei Shouliu +3 more
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Fractional matching preclusion for butterfly derived networks
Theory and Applications of Graphs, 2019 The matching preclusion number of a graph is the minimum number of edges whose deletion results in a graph that has neither perfect matchings nor almost perfect matchings.
Xia Wang +4 more
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Formation of Non-Perfect Maze Using Prim’s Algorithm
JTAM (Jurnal Teori dan Aplikasi Matematika), 2023 Maze is a place that has many paths with tortuous paths that are misleading and full of dead ends and can be viewed as a grid graph. A non-perfect maze is a maze that has a cycle.
Mahyus Ihsan +4 more
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