Fuente TeX:

\begin{align}(P) \ \ z = prox_{\lambda_{g} g} = argmin_{x} \ & \frac{1}{2\lambda_g} \left \| x - z \right \|^2 + g(x)\ \leftrightarrow \frac{1}{\lambda_g} (z-v) + \nabla g(z) = 0 \rightarrow v-z= \lambda_g \nabla g(z) \end{align}