弱的程度有多弱?
How weak is weak extent?
摘要:
一个空间X是星-林德洛夫空间,对于每个开覆盖U,存在X的有限子集A使得St(A,U)=X。我们证明了一个Tychonoff星Lindelof空间可以有任意大的范围,而一个正常的星Lindelof空间的范围不能大于c.
英文摘要:
A space X is star-Lindelof provided for every open cover U there is a finite subset A of X such that St(A,U)=X. We show that a Tychonoff star-Lindelof space can have arbitraryly big extent while the extent of a normal star-Lindelof space can not be greater than c.
机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。