Top > T_D


Last-modified: 2013-04-19 (金) 13:23:36

Definition Edit

  • A topological space is said to be T_D if for every point x of X, imgtex.fcgi?%5bres=100%5d%7b%5c%5b%20%5c%7bx%5c%7d'%20%5c%5d%7d%25.png (the derived set of {x}) is a closed set.

Property Edit

Reference Edit

  1. Aull, Charles E.; Thron, W.J.,Separation axioms between T0 and T1., (English) [J] Nederl. Akad. Wet., Proc., Ser. A 65, 26-37 (1962).
  2. Misra, D. N.; Dube, K. K., Some axioms weaker than the R0-axiom., (Serbo-Croatian summary), Glasnik Mat. Ser. III 8(28) (1973), 145-148.
  3. Guia, Josep, Essentially T_D and essentially T_UD spaces., Bull. Math. Soc. Sci. Math. R. S. Roumanie (N.S.) 32(80) (1988), no. 3, 227-233.