character

Last-modified: 2011-08-12 (金) 02:47:35

Definition

For a topological space X, the character of x in X is defined by

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The character of X is defined by

imgtex.fcgi?%5bres=100%5d%7b%5c%5b%20%5cchi%28X%29=%5csup%5c%7b%5cchi%28x%2cX%29:x%5cin%20X%5c%7d%20%5c%5d%7d%25.png

Reference

K.P.Hart, J. Nagata and J.E. Vaughan, Encyclopedia of general topology, Elsevier Science