Association schemes generated by a non-symmetric relation of valency 2

نویسندگان

  • Mitsugu Hirasaka
  • Mikhail E. Muzychuk
چکیده

We give some observations on association schemes with a relation of valency 2 from the representation theory of Bose–Mesner algebras and the basic structure theory. One of the applications of these observations is the classi-cation of the association schemes with a non-symmetric relation of valency 2 if the cardinality of the point set is a product of two primes, and another is the proof of Li’s conjecture that any -nite simple group is a connected 2-DCI-group. c © 2002 Elsevier Science B.V. All rights reserved.

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عنوان ژورنال:
  • Discrete Mathematics

دوره 244  شماره 

صفحات  -

تاریخ انتشار 2002