摘要
In this paper, we mainly discuss the images of certain spaces under closed sequencecovering maps. It is showed that the property with a locally countable weak base is preserved by closed sequence-covering maps. And the following question is discussed： Are the closed sequence-covering images of spaces with a point-countable sn-network sn-first countable？
In this paper, we mainly discuss the images of certain spaces under closed sequencecovering maps. It is showed that the property with a locally countable weak base is preserved by closed sequence-covering maps. And the following question is discussed： Are the closed sequence-covering images of spaces with a point-countable sn-network sn-first countable？
基金
Supported by National Natural Science Foundation of China (Grant Nos.11201414
10971185
11171162)
the Natural Science Foundation of Fujian Province (Grant No.2012J05013)
Training Programme Foundation for Excellent Youth Researching Talents of Fujian’s Universities (Grant No.JA13190)
