The second order elliptic partial differential equations are considered in an exterior domain,some new sufficient conditions for oscillation of all solutions of the equation are obtained by the sequence of functions.
利用函数序列方法，得到了保证二阶椭圆型微分方程在外区域Ω上一切解振动的新的充分条件。
It is composed of an outer-sequence with an m sequence and inner-sequences with Walsh sequences.
它由外部序列和内部序列组成,外部序列是一个 m 序列,内部序列是几个 Walsh 函数序列构成。