On designs related to coherent configurations of type \((^ 2\;^ 2_ 4)\). (English) Zbl 0756.05013

Hobart, S. A.

Discrete Math. 94, No. 2, 103-127 (1991).

Coherent configurations were earlier studied by D. G. Higman [Linear Algebra Appl. 93, 209-239 (1987; Zbl 0618.05014)]. The parametric relations for the coherent configurations of type \(\left({2\atop\;}{2\atop n}\right)\) and related designs are established here. It is shown that the Witt design \({\mathcal S}(5,8,24)\) is determined by the association scheme on its blocks and the family of designs based on systems of linked symmetric designs is characterized.

Reviewer: K.Sinha (Ranchi)

MSC:

05B05	Combinatorial aspects of block designs
05B30	Other designs, configurations
05E30	Association schemes, strongly regular graphs

Keywords:

coherent configurations; Witt design; association scheme; symmetric designs

Citations:

Zbl 0618.05014

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