
答え1
@Bernard の回答の小さなバリエーション (+1):
\documentclass{article}
\usepackage{enumitem}
\usepackage{lipsum}
\begin{document}
\begin{enumerate}[wide=0pt, label =(\arabic*)]
\item \hfil$r_1,,r_2,\dots, r_{\varphi(m)} $
-- \lipsum[66]
\item \hfil$\rho_{k} \equiv r_{k}\pmod{m} $
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\end{enumerate}
\end{document}
答え2
考えられる解決策は次のとおりです:
\documentclass{article}
\usepackage{enumitem}
\usepackage{lipsum}
\begin{document}
\begin{enumerate}[wide=0pt, label =(\arabic*), parsep = 1ex]
\item \makebox[\linewidth]{$r_1,,r_2,\dots, r_{\varphi(m)} $}
\lipsum[11]
\item \makebox[\linewidth]{$\rho_{k} \equiv r_{k}\pmod{m} $}
\lipsum[11]
\end{enumerate}
\end{document}