As a kind of completeorthogonal polynomial system, U system has many good properties such as orthogonality and convergence.
作为一种可选定次数的完备正交多项式系统，U系统所定义的矩具有标准正交性、收敛性等优良性质。
2
In order to solve the problem of completesystem of orthogonal Latin squares, relation between Latin square and permutation groups is discussed by using method of algebra.