A Family of Antipodal Distance-Regular Graphs Related to the Classical Preparata Codes
نویسنده
چکیده
A new family of distance-regular graphs is constructed. They are antipodal 2 -fold covers of the complete graph on 2 vertices. The automorphism groups are determined, and the extended Preparata codes are reconstructed using walks on these graphs. There are connections to other interesting structures: the graphs are equivalent to certain generalized Hadamard matrices; and their underlying 3-class association scheme is formally dual to the scheme of a system of linked symmetric designs obtained from Kerdock sets of skew matrices in characteristic two.
منابع مشابه
A Family of Antipodal Distance-Regular Graphs Related to the Classical Preparata Codes
A new family of distance-regular graphs is constructed. They are antipodal 22t−1-fold covers of the complete graph on 22t vertices. The automorphism groups are determined, and the extended Preparata codes are reconstructed using walks on these graphs. There are connections to other interesting structures: the graphs are equivalent to certain generalized Hadamard matrices; and their underlying 3...
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تاریخ انتشار 2003