ON A COUNTABLE BASE AND THE CONJUGATE CLASS OF A TOPOLOGICAL SPACE
P L Ul'janov · Mathematics of the USSR-Sbornik · 1976
In this paper the classes of functions are studied, and the topological spaces are constructed from them. In particular, a necessary and sufficient condition guaranteeing a countable base in is found. Classes of functions conjugate (relative to sum) to are introduced and investigated.Bibliography: 7 titles.