Equation 3.1.1449DB76D43578

\begin{equation} E_ d(x)=\begin{cases} |x|/2,& d=1,\\ (2\pi )^{-1}\log |x|,& d=2,\\ -((d-2)s_{d-1})^{-1}|x|^{2-d},& d\geq 3 \end{cases} \end{equation}