它可能会帮助你:
\documentclass{article}
\usepackage{amsmath}
\usepackage{lipsum} % for dummy text
\begin{document}
\lipsum[11]
\begin{gather*}
(P) \qquad\begin{aligned}
\min &\quad f(x) \\
\mathrm{s.t} &\quad g(x,s)\leq 0\:\:\forall s\in\Omega
\end{aligned}
\end{gather*}
\lipsum[12]
\end{document}