Dimension of the sum of two copies of a graph
Dimers and cluster integrable systems
We show that the dimer model on a bipartite graph on a torus gives rise to a quantum integrable system of special type, which we call acluster integrable system. The phase space of the classical system contains, as an open dense subset, the moduli space of line bundles with connections on the graph . The sum of Hamiltonians is essentially the partition function of the dimer model. We say that two such graphs and areequivalentif the Newton polygons of the corresponding partition functions...
Dirac type condition and Hamiltonian graphs
2010 Mathematics Subject Classification: 05C38, 05C45.In 1952, Dirac introduced the degree type condition and proved that if G is a connected graph of order n і 3 such that its minimum degree satisfies d(G) і n/2, then G is Hamiltonian. In this paper we investigate a further condition and prove that if G is a connected graph of order n і 3 such that d(G) і (n-2)/2, then G is Hamiltonian or G belongs to four classes of well-structured exceptional graphs.
Direct enumeration of chiral and achiral graphs of a polyheterosubstituted monocyclic cycloalkane.
Direct product decompositions of digraphs
Direct product decompositions of -digraphs
Direct products of cyclic semigroups admitting a planar Cayley graph.
Directed and antidirected Hamiltonian cycles and paths in bipartite graphs
Directed forests with application to algorithms related to Markov chains
This paper is devoted to computational problems related to Markov chains (MC) on a finite state space. We present formulas and bounds for characteristics of MCs using directed forest expansions given by the Matrix Tree Theorem. These results are applied to analysis of direct methods for solving systems of linear equations, aggregation algorithms for nearly completely decomposable MCs and the Markov chain Monte Carlo procedures.
Directed graphs and matrix equations
Directed hypergraphs: a tool for researching digraphs and hypergraphs
In this paper we introduce the concept of directed hypergraph. It is a generalisation of the concept of digraph and is closely related with hypergraphs. The basic idea is to take a hypergraph, partition its edges non-trivially (when possible), and give a total order to such partitions. The elements of these partitions are called levels. In order to preserve the structure of the underlying hypergraph, we ask that only vertices which belong to exactly the same edges may be in the same level...
Directed pseudo-graphs and Lie algebras over finite fields
The main goal of this paper is to show an application of Graph Theory to classifying Lie algebras over finite fields. It is rooted in the representation of each Lie algebra by a certain pseudo-graph. As partial results, it is deduced that there exist, up to isomorphism, four, six, fourteen and thirty-four -, -, -, and -dimensional algebras of the studied family, respectively, over the field . Over , eight and twenty-two - and -dimensional Lie algebras, respectively, are also found. Finally,...
Directed subgraph complexes.
Direction Trees.
Disconnected neighbourhood graphs
Disconnected vertex sets and equidistant code pairs.
Discovering hook length formulas by an expansion technique.
Discrepancy and eigenvalues of Cayley graphs
We consider quasirandom properties for Cayley graphs of finite abelian groups. We show that having uniform edge-distribution (i.e., small discrepancy) and having large eigenvalue gap are equivalent properties for such Cayley graphs, even if they are sparse. This affirmatively answers a question of Chung and Graham (2002) for the particular case of Cayley graphs of abelian groups, while in general the answer is negative.
Discrepancy games.
Discrepancy of symmetric products of hypergraphs.