A family of tridiagonal pairs related to the quantum affine algebra .
A Fan-Type Heavy Pair Of Subgraphs For Pancyclicity Of 2-Connected Graphs
Let G be a graph on n vertices and let H be a given graph. We say that G is pancyclic, if it contains cycles of all lengths from 3 up to n, and that it is H-f1-heavy, if for every induced subgraph K of G isomorphic to H and every two vertices u, v ∈ V (K), dK(u, v) = 2 implies [...] mindG(u),dG(v)≥n+12 . In this paper we prove that every 2-connected K1,3, P5-f1-heavy graph is pancyclic. This result completes the answer to the problem of finding f1-heavy pairs of subgraphs implying pancyclicity...
A fast algorithm for MacMahon's partition analysis.
A fast multi-scale method for drawing large graphs.
A few more cyclic Steiner 2-designs.
A few remarks on the history of MST-problem
On the background of Borůvka’s pioneering work we present a survey of the development related to the Minimum Spanning Tree Problem. We also complement the historical paper Graham-Hell [GH] by a few remarks and provide an update of the extensive literature devoted to this problem.
A Fiedler-like theory for the perturbed Laplacian
The perturbed Laplacian matrix of a graph is defined as , where is any diagonal matrix and is a weighted adjacency matrix of . We develop a Fiedler-like theory for this matrix, leading to results that are of the same type as those obtained with the algebraic connectivity of a graph. We show a monotonicity theorem for the harmonic eigenfunction corresponding to the second smallest eigenvalue of the perturbed Laplacian matrix over the points of articulation of a graph. Furthermore, we use...
A Finite Characterization and Recognition of Intersection Graphs of Hypergraphs with Rank at Most 3 and Multiplicity at Most 2 in the Class of Threshold Graphs
We characterize the class [...] L32 of intersection graphs of hypergraphs with rank at most 3 and multiplicity at most 2 by means of a finite list of forbidden induced subgraphs in the class of threshold graphs. We also give an O(n)-time algorithm for the recognition of graphs from [...] L32 in the class of threshold graphs, where n is the number of vertices of a tested graph.
A Foata bijection for the alternating group and for -analogues.
A forbidden subgraphs characterization and a polynomial algorithm for randomly decomposable graphs
A forbidden-suborder characterization of binarily-composable diagrams in double categories.
A formula for all minors of the adjacency matrix and an application
We supply a combinatorial description of any minor of the adjacency matrix of a graph. This description is then used to give a formula for the determinant and inverse of the adjacency matrix, A(G), of a graph G, whenever A(G) is invertible, where G is formed by replacing the edges of a tree by path bundles.
A formula for the bivariate map asymptotics constants in terms of the univariate map asymptotics constants.
A formula for the generating functions of powers of Horadam's sequence with two additional parameters.
A four-class association scheme derived from a hyperbolic quadric in .
A Frobenius formula for the characters of the Hecke algebras.
A functional combinatorial central limit theorem.
A further application of matrix analysis to communication structure in oceanic anthropology
A further look into combinatorial orthogonality.
A Gallai-type equality for the total domination number of a graph
We prove the following Gallai-type equality γₜ(G) + εₜ(G) = p for any graph G with no isolated vertex, where p is the number of vertices of G, γₜ(G) is the total domination number of G, and εₜ(G) is the maximum integer s such that there exists a spanning forest F with s the number of pendant edges of F minus the number of star components of F.