【摘要】 证明了几乎次亚lindelf、可数紧度的可数紧X是紧空间.定义了几乎强次亚紧空间,给出了它的一个刻画,并证明了几乎强次亚紧、可数紧T3-空间是紧空间.更多还原

【Abstract】 A countable compact and nearly submeta-lindelf space with countable tightness are proved to be compact.The nearly strongly submetacompact space is defined and one of its characterizations is given.The nearly strongly submetacompact and the countable compact T3-space are proved to be compact.更多还原