We consider regular hypoelliptic operators and study some properties of completely regular polyhedra. Basing on the obtained properties, we find an upper bound for the functional dimension of the solution spaces of hypoelliptic equations.

中文翻译：

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一类次椭圆方程的符号性质

我们考虑正则椭圆椭圆算子，并研究完全正则多面体的一些性质。基于获得的性质，我们找到次椭圆方程解空间的函数维数的上限。