is the unit -ball.
:

In general, and are given in closed form by the expressions

where is the gamma function. Note that 's values at half-integers contain a factor of that cancels out the factor in the numerator.

As tends to infinity, the volume of the unit -ball (ratio between the volume of an -ball of radius and an {{tmath of side length ) tends to zero.

Recurrences

The surface area, or properly the -dimensional