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Distance-Regular Graphs

TLDR
In this paper, a connected simple graph with vertex set X of diameter d is considered, and the authors define Ri X2 by (x, y) Ri whenever x and y have graph distance.
Abstract
Consider a connected simple graph with vertex set X of diameter d. Define Ri X2 by (x, y) Ri whenever x and y have graph distance

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Quasi-Spectral Characterization of Strongly Distance-Regular Graphs

TL;DR: A characterization of strongly regular graphs with diameter d in terms of the eigenvalues, the sum of the multiplicities corresponding to the Eigenvalues with (non-zero) even subindex, and the harmonic mean of the degrees of the distance-$d$ graph.
Journal ArticleDOI

Algebraic methods for chromatic polynomials

TL;DR: An explicit formula for mπ (k) is derived and a method for calculating the matrices NLπ is described, where nπ is the degree of the representation Rπ of Syml associated with π, and the square matrix NLπ has size (b l)nπ.
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A Higman inequality for regular near polygons

TL;DR: In this paper, the intersection number c i of a regular near 2d-gon of order (s,t) with s>1 satisfies the tight bound c i?(s 2i?1)/( s 2?1), and properties in case of equality.
Posted Content

Lecture notes: Semidefinite programs and harmonic analysis

TL;DR: Lecture notes for the tutorial at the workshop HPOPT 2008 - 10th International Workshop on High Performance Optimization Techniques (Algebraic Structure in Semidefinite Programming)
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Some properties of the twisted Grassmann graphs

TL;DR: In this article, the full automorphism group of the twisted Grassmann graph was determined and it was shown that the twisted grassmann graphs do not have antipodal distance-regular covers.
References
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Equilateral point sets in elliptic geometry

TL;DR: In this paper, the authors highlight equilateral point sets in elliptic geometry and show that Paley's construction may be reversed to obtain a C -matrix of order 46, in view of the existence of a Hadamard matrix of order 92.
BookDOI

On construction and identification of graphs

B. Weisfeiler
TL;DR: The problem of graph identification has been studied in the theory of permutation groups for a long time, see as mentioned in this paper for a discussion of the main points of the problem and an algorithm for graph identification.