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Related papers: Unmixed bipartite graphs

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Unmixed bipartite graphs have been characterized by Ravadra and Villarreal independently. Our aim in this paper is to characterize unmixed r-partite graphs under a certain condition, witch is a generalization of villarreal's theorem on…

Combinatorics · Mathematics 2015-11-03 Reza Jafarpoure Golzari , Rashid Zaare-Nahandi

A classification is given of all the countable homogeneous ordered bipartite graphs.

Combinatorics · Mathematics 2024-01-17 J. K. Truss

Using the theory of combinatorial species, we compute the cycle index for bipartite graphs, which we use to count unlabeled bipartite graphs and bipartite blocks.

Combinatorics · Mathematics 2015-09-14 Andrew Gainer-Dewar , Ira M. Gessel

In this paper, we completely characterize the niche graphs of bipartite tournaments and find their interesting properties.

Combinatorics · Mathematics 2018-10-15 Soogang Eoh , Jihoon Choi , Suh-Ryung Kim , Miok Oh

For an unmixed bipartite graph $G$ we consider the lattice of vertex covers $\mathcal{L}_G$ and compute depth, projective dimension and extremal Betti-numbers of $R/I(G)$ in terms of this lattice.

Commutative Algebra · Mathematics 2009-01-21 Fatemeh Mohammadi , Somayeh Moradi

In this paper, we characterize all unmixed d-uniform r-partite hypergraphs under a certain condition. Also we give a necessary condition for unmixedness in d-uniform hypergraphs with a perfect matching of size n. Finally we give a…

Commutative Algebra · Mathematics 2016-10-04 Reza Jafarpour-Golzari , Rashid Zaare-Nahandi

We introduce a new notation for representing labeled regular bipartite graphs of arbitrary degree. Several enumeration problems for labeled and unlabeled regular bipartite graphs have been introduced. A general algorithm for enumerating all…

Discrete Mathematics · Computer Science 2015-12-31 Vivek S. Nittoor

We show that the independent set sequence of a bipartite graph need not be unimodal.

Combinatorics · Mathematics 2013-01-10 Arnab Bhattacharyya , Jeff Kahn

Motivated by the concept of well-covered graphs, we define a graph to be well-bicovered if every vertex-maximal bipartite subgraph has the same order (which we call the bipartite number). We first give examples of them, compare them with…

Combinatorics · Mathematics 2019-09-18 Wayne Goddard , Kirsti Kuenzel , Eileen Melville

We give a combinatorial characterization of graphs whose normalized Laplacian has three distinct eigenvalues. Strongly regular graphs and complete bipartite graphs are examples of such graphs, but we also construct more exotic families of…

Combinatorics · Mathematics 2012-02-15 Edwin R. van Dam , Gholamreza Omidi

The correspondence between unmixed bipartite graphs and sublattices of the oolean lattice is discussed. By using this correspondence, we show the existence of squarefree quadratic initial ideals of toric ideals arising from minimal vertex…

Commutative Algebra · Mathematics 2019-01-11 Juergen Herzog , Takayuki Hibi , Hidefumi Ohsugi

Classical spectral graph theory characterizes graphs with logarithmic mixing time. In this work, we present a combinatorial characterization of graphs with constant mixing time. The combinatorial characterization is based on the small-set…

Data Structures and Algorithms · Computer Science 2025-12-02 Lap Chi Lau , Raymond Liu

In this paper, we classify the connected non-bipartite integral graphs with spectral radius three.

Combinatorics · Mathematics 2011-06-23 Taeyoung Chung , Jack Koolen , Yoshio Sano , Tetsuji Taniguchi

This paper deals with the problem of finding totally antimagic total labelings of complete bipartite graphs. We prove that complete bipartite graphs are totally antimagic total graphs. We also show that the join of complete bipartite graphs…

Combinatorics · Mathematics 2016-08-25 Abolape D. Akwu , Deborah O. A. Ajayi

In this paper we consider bi-Cohen-Macaulay graphs, and give a complete classification of such graphs in the case they are bipartite or chordal. General bi-Cohen-Macaulay graphs are classified up to separation. The inseparable…

Commutative Algebra · Mathematics 2015-08-31 Jürgen Herzog , Ahad Rahimi

The total matching polytope generalizes the stable set polytope and the matching polytope. In this paper, we first propose new facet-defining inequalities for the total matching polytope. We then give an exponential-sized, non-redundant…

Discrete Mathematics · Computer Science 2023-12-29 Yuri Faenza , Luca Ferrarini

This paper is a survey on Extremal Graph Theory, primarily focusing on the case when one of the excluded graphs is bipartite. On one hand we give an introduction to this field and also describe many important results, methods, problems, and…

Combinatorics · Mathematics 2013-07-02 Zoltán Füredi , Miklós Simonovits

A split graph is a graph whose vertices can be partitioned into a clique and a stable set. We investigate the combinatorial species of split graphs, providing species-theoretic generalizations of enumerative results due to B\'ina and…

Combinatorics · Mathematics 2019-07-16 Justin M. Troyka

It is not hard to find many complete bipartite graphs which are not determined by their spectra. We show that the graph obtained by deleting an edge from a complete bipartite graph is determined by its spectrum. We provide some graphs, each…

Combinatorics · Mathematics 2016-01-27 Chia-an Liu , Chih-wen Weng

We classify which complete multipartite graphs are intrinsically chiral.

Geometric Topology · Mathematics 2013-03-22 Erica Flapan , Will Fletcher
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