Generalized Krein Parameters of a Strongly Regular Graph

Lus Almeida Vieira¹, Vasco Moço Mano²

¹CMUP—Center of Research of Mathematics of University of Porto, Department of Civil Engineering, University of Porto, Porto, Portugal.
²CIDMA—Center for Research and Development in Mathematics and Applications, Department of Mathematics, University of Aveiro, Aveiro, Portugal.

DOI: 10.4236/am.2015.61005                

Abstract

We consider the real three-dimensional Euclidean Jordan algebra associated to a strongly regular graph. Then, the Krein parameters of a strongly regular graph are generalized and some generalized Krein admissibility conditions are deduced. Furthermore, we establish some relations between the classical Krein parameters and the generalized Krein parameters.

Keywords

Algebraic Combinatorics, Association Schemes, Strongly Regular Graphs, Graphs and Linear Algebra

Conflicts of Interest

The authors declare no conflicts of interest.

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