Strongly Regular Graphs Arising From Balanced Incomplete Block Design With λ = 1
نویسنده
چکیده
In [M. Klin, A. Munemusa, M. Muzychuk, P.-H. Zieschang Directed strongly regular graphs obtained from coherent algebras. Linear Algebra and its Applications 337, (2004) 83-109] the flag algebra of a given balanced incomplete block design with parameters (ν, b, r, k, λ) where λ = 1, has been constructed. In this paper, we consider the association scheme which is related to this flag algebra. By quotient scheme of this association scheme, we construct a strongly regular graph which its parameters are related to the parameters of given balanced incomplete block design. The parameters of this strongly regular graph are ( kr − r + r k , k(r − 1), r − 2 + (k − 1), k).
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