A NECESSARY CONDITION FOR ANALYTIC HYPOELLIPTIC PSEUDO-HOMOGENEOUS PARTIAL DIFFERENTIAL OPERATORS
拟齐次解析亚椭圆偏微分算子的一个必要条件

This paper gives a necessary condition for a linear partial differential operator P(x,D), which is homogeneous with respect to some dilations, to be analytic hypoelliptic at the origin as follows: Assume u implied by S'_(#mu#,#lambda#)(R~n)(for S'_(#mu#,#lambda#)R~n, see Introduction) and Pu=0. Then there exists an entire function v satisfying Pv=0 where v is consistent with u in some neighborhood of x=0.