About the Center of Some Types of Sub algebra of Full Matrix Algebra

Based on the theory of finite dimensional algebra and the nature of matrix in field K, the centers of some sub algebras, such as the diagonal matrix algebra D_n(K), Jordan algebra J_n(K), upper-triangular matrix algebra T_n(K) and sub algebra generated by K[A] of complete matrix algebra M_n(K) in field K are presented in this paper.