# ON 4-EQUIVALENCED ASSOCIATION SCHEMES

• 투고 : 2014.11.19
• 발행 : 2015.09.30

#### 초록

Let (${\Omega}$, S) be an association scheme where ${\Omega}$ is a non-empty finite set and S is a partition of ${\Omega}{\times}{\Omega}$. For a positive integer k we say that (${\Omega}$, S) is k-equivalenced if each non-diagonal element of S has valency k. In this paper we focus on 4-equivalenced association schemes, and prove that they are transitive.

#### 참고문헌

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