The underlying set of the fundamental group of is the set of based homotopy classes from the circle to , denoted . For general spaces and , there is no natural group structure on , but when there is a natural group structure, is called a co--space.

# Co-H-Space

## See also

Co-H-Group, Fundamental Group, H-Space, Homotopy Class## Explore with Wolfram|Alpha

## Cite this as:

Weisstein, Eric W. "Co-H-Space." From
*MathWorld*--A Wolfram Web Resource. https://mathworld.wolfram.com/Co-H-Space.html