On the nomura algebras of formally self-dual association schemes of class $2$

Document Type: Research Paper

Authors

1 Department of Mathematics, K. N. Toosi University of Technology

2 K. N. Toosi university of Technology University, Tehran-Iran.

Abstract

‎‎In this paper‎, ‎the type-II matrices on (negative) Latin square graphs are considered and it is proved that‎, ‎under‎ ‎certain conditions‎, ‎the Nomura algebras of such type-II matrices are trivial‎. ‎In addition‎, ‎we construct type-II matrices‎ ‎on doubly regular tournaments and show that the Nomura algebras of such matrices are also trivial‎.

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