English
Related papers

Related papers: On some Graphs with a Unique Perfect Matching

200 papers

For any graph $G$ on $n$ vertices and for any {\em symmetric} subgraph $J$ of $K_{n,n}$, we construct an infinite sequence of graphs based on the pair $(G,J)$. The First graph in the sequence is $G$, then at each stage replacing every…

Combinatorics · Mathematics 2013-10-10 Kiran B. Chilakamarri , M. F. Khan , C. E. Larson , C. J. Tymczak

We present a deterministic algorithm which, given a graph G with n vertices and an integer 1<m < n, computes in n^{O(ln m)} time the sum of weights w(S) over all m-subsets S of the set of vertices of G, where w(S)=exp{gamma t m +O(1/m)}…

Combinatorics · Mathematics 2014-10-15 Alexander Barvinok

Homomorphically full graphs are those for which every homomorphic image is isomorphic to a subgraph. We extend the definition of homomorphically full to oriented graphs in two different ways. For the first of these, we show that…

Discrete Mathematics · Computer Science 2024-02-14 Thomas Bellitto , Christopher Duffy , Gary MacGillivray

Let G and H be two cographs. We show that the problem to determine whether H is a retract of G is NP-complete. We show that this problem is fixed-parameter tractable when parameterized by the size of H. When restricted to the class of…

Discrete Mathematics · Computer Science 2013-03-26 Ton Kloks , Yue-Li Wang

We consider random perfect matchings on a general class of contracting bipartite graphs by letting certain edge weights be 0 on the contracting square-hexagon lattice in a periodic way. We obtain a deterministic limit shape in the scaling…

Probability · Mathematics 2021-01-07 Zhongyang Li

A matching cut is a matching that is also an edge cut. In the problem Minimum Matching Cut, we ask for a matching cut with the minimum number of edges in the matching. We investigate the differences in complexity between Minimum Matching…

Combinatorics · Mathematics 2026-02-20 Felicia Lucke , Joseph Marchand , Jannik Olbrich

Temporal graphs are graphs where the topology and/or other properties of the graph change with time. They have been used to model applications with temporal information in various domains. Problems on static graphs become more challenging…

Data Structures and Algorithms · Computer Science 2022-02-02 Subhrangsu Mandal , Arobinda Gupta

Perfect matchings and maximum weight matchings are two fundamental combinatorial structures. We consider the ratio between the maximum weight of a perfect matching and the maximum weight of a general matching. Motivated by the computer…

Discrete Mathematics · Computer Science 2018-11-08 Emilio Vital Brazil , Guilherme D. da Fonseca , Celina de Figueiredo , Diana Sasaki

We give alternative definitions for maximum matching width, e.g. a graph $G$ has $\operatorname{mmw}(G) \leq k$ if and only if it is a subgraph of a chordal graph $H$ and for every maximal clique $X$ of $H$ there exists $A,B,C \subseteq X$…

Data Structures and Algorithms · Computer Science 2015-07-10 Jisu Jeong , Sigve Hortemo Sæther , Jan Arne Telle

A nontrivial connected graph is matching covered if each edge belongs to some perfect matching. For most problems pertaining to perfect matchings, one may restrict attention to matching covered graphs; thus, there is extensive literature on…

Combinatorics · Mathematics 2025-11-10 Rohinee Joshi , Santhosh Raghul , Nishad Kothari

A \emph{long unichord} in a graph is an edge that is the unique chord of some cycle of length at least 5. A graph is \emph{long-unichord-free} if it does not contain any long-unichord. We prove a structure theorem for long-unichord-free…

Discrete Mathematics · Computer Science 2023-10-23 Lan Anh Pham , Nicolas Trotignon

Proper conflict-free coloring is an intermediate notion between proper coloring of a graph and proper coloring of its square. It is a proper coloring such that for every non-isolated vertex, there exists a color appearing exactly once in…

Combinatorics · Mathematics 2024-12-16 Chun-Hung Liu

An $H$-graph is an intersection graph of connected subgraphs of a suitable subdivision of a fixed graph $H$. Many important classes of graphs, including interval graphs, circular-arc graphs, and chordal graphs, can be expressed as…

Data Structures and Algorithms · Computer Science 2022-06-28 Deniz Ağaoğlu Çağırıcı , Peter Zeman

IC-planar graphs are those graphs that admit a drawing where no two crossed edges share an end-vertex and each edge is crossed at most once. They are a proper subfamily of the 1-planar graphs. Given an embedded IC-planar graph $G$ with $n$…

Computational Geometry · Computer Science 2016-07-19 Franz J. Brandenburg , Walter Didimo , William S. Evans , Philipp Kindermann , Giuseppe Liotta , Fabrizio Montecchiani

This paper is concerned with structures of general graphs with perfect matchings. We first reveal a partially ordered structure among factor-components of general graphs with perfect matchings. Our second result is a generalization of…

Discrete Mathematics · Computer Science 2013-03-26 Nanao Kita

A graph is CIS if every maximal clique interesects every maximal stable set. Currently, no good characterization or recognition algorithm for the CIS graphs is known. We characterize graphs in which every maximal matching saturates all…

Combinatorics · Mathematics 2018-12-14 Liliana Alcón , Marisa Gutierrez , Martin Milanič

The approach mapping from a matching of bipartite graphs to digraphs has been successfully used for forcing set problem, in this paper, it is extended to uniquely restricted matching problem. We show to determine a uniquely restricted…

Computational Complexity · Computer Science 2010-09-29 Guohun Zhu

A graph is path-pairable if for any pairing of its vertices there exist edge disjoint paths joining the vertices in each pair. We obtain sharp bounds on the maximum possible diameter of path-pairable graphs which either have a given number…

Combinatorics · Mathematics 2017-07-14 Antonio Girao , Gabor Meszaros , Kamil Popielarz , Richard Snyder

A graph is said to be orthogonalisable if the set of real symmetric matrices whose off-diagonal pattern is prescribed by its edges contains an orthogonal matrix. We determine some necessary and some sufficient conditions on the sizes of the…

Combinatorics · Mathematics 2025-06-16 Rupert H. Levene , Polona Oblak , Helena Šmigoc

Exact pattern matching in labeled graphs is the problem of searching paths of a graph $G=(V,E)$ that spell the same string as the pattern $P[1..m]$. This basic problem can be found at the heart of more complex operations on variation graphs…

Computational Complexity · Computer Science 2020-06-04 Massimo Equi , Roberto Grossi , Veli Mäkinen
‹ Prev 1 4 5 6 7 8 10 Next ›