countably infinite 可数无限

countably compact 可数紧的

countably additive class 可数加性类

countably additive family 可数加性族

countably additive function 可数加性的函数

countably subadditive function 可数次可加性的函数

relatively countably compact subset 相对可数紧子集

countably superadditive function 可数超加性函数

countably semi additive function 可数半加性的函数