Usei um Jornal da AMS no Sharelatex e apareceu o pi.
Faltou um minimal working example (MWE) para que possamos ajudá-lo mais precisamente.
Att,
Emílio E. Kavamura,MSc
DeGraf - UFPR
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\newtheorem{theorem}{Theorem}[section]
\newtheorem{lemma}[theorem]{Lemma}
\theoremstyle{definition}
\newtheorem{definition}[theorem]{Definition}
\newtheorem{example}[theorem]{Example}
\newtheorem{xca}[theorem]{Exercise}
\theoremstyle{remark}
\newtheorem{remark}[theorem]{Remark}
\numberwithin{equation}{section}
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\title{AMS Journal Sample}
% Information for first author
\author{Author One}
% Address of record for the research reported here
\address{Department of Mathematics, Louisiana State University, Baton
Rouge, Louisiana 70803}
% Current address
\curraddr{Department of Mathematics and Statistics,
Case Western Reserve University, Cleveland, Ohio 43403}
\
email{x...@math.university.edu}
% \thanks will become a 1st page footnote.
\thanks{The first author was supported in part by NSF Grant \#000000.}
% Information for second author
\author{Author Two}
\address{Mathematical Research Section, School of Mathematical Sciences,
Australian National University, Canberra ACT 2601, Australia}
\
email{t...@maths.univ.edu.au}
\thanks{Support information for the second author.}
% General info
\subjclass[2000]{Primary 54C40, 14E20; Secondary 46E25, 20C20}
\date{January 1, 2001 and, in revised form, June 22, 2001.}
\dedicatory{This paper is dedicated to our advisors.}
\keywords{Differential geometry, algebraic geometry}
\begin{abstract}
This paper is a sample prepared to illustrate the use of the American
Mathematical Society's \LaTeX{} document class \texttt{amsart} and
publication-specific variants of that class for AMS-\LaTeX{} version 2.
\end{abstract}
\maketitle
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$\pi$
\[\pi\]
\begin{align*}
\pi
\end{align*}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%\section*{This is an unnumbered first-level section head}
This is an example of an unnumbered first-level heading.
%% The correct journal style for \specialsection is all uppercase; a known bug
%% in amsart.cls prevents this, so input must be uppercase until it is fixed.
%\specialsection*{This is a Special Section Head}
\specialsection*{THIS IS A SPECIAL SECTION HEAD}
This is an example of a special section head%
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\footnote{Here is an example of a footnote. Notice that this footnote
text is running on so that it can stand as an example of how a footnote
with separate paragraphs should be written.
\par
And here is the beginning of the second paragraph.}%
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.
\section{This is a numbered first-level section head}
This is an example of a numbered first-level heading.
\subsection{This is a numbered second-level section head}
This is an example of a numbered second-level heading.
\subsection*{This is an unnumbered second-level section head}
This is an example of an unnumbered second-level heading.
\subsubsection{This is a numbered third-level section head}
This is an example of a numbered third-level heading.
\subsubsection*{This is an unnumbered third-level section head}
This is an example of an unnumbered third-level heading.
\begin{lemma}
Let $f, g\in A(X)$ and let $E$, $F$ be cozero
sets in $X$.
\begin{enumerate}
\item If $f$ is $E$-regular and $F\subseteq E$, then $f$ is $F$-regular.
\item If $f$ is $E$-regular and $F$-regular, then $f$ is $E\cup
F$-regular.
\item If $f(x)\ge c>0$ for all $x\in E$, then $f$ is $E$-regular.
\end{enumerate}
\end{lemma}
The following is an example of a proof.
\begin{proof} Set $j(\nu)=\max(I\backslash a(\nu))-1$. Then we have
\[
\sum_{i\notin a(\nu)}t_i\sim t_{j(\nu)+1}
=\prod^{j(\nu)}_{j=0}(t_{j+1}/t_j).
\]
Hence we have
\begin{equation}
\begin{split}
\prod_\nu\biggl(\sum_{i\notin
a(\nu)}t_i\biggr)^{\abs{a(\nu-1)}-\abs{a(\nu)}}
&\sim\prod_\nu\prod^{j(\nu)}_{j=0}
(t_{j+1}/t_j)^{\abs{a(\nu-1)}-\abs{a(\nu)}}\\
&=\prod_{j\ge 0}(t_{j+1}/t_j)^{
\sum_{j(\nu)\ge j}(\abs{a(\nu-1)}-\abs{a(\nu)})}.
\end{split}
\end{equation}
By definition, we have $a(\nu(j))\supset c(j)$. Hence, $\abs{c(j)}=n-j$
implies (5.4). If $c(j)\notin a$, $a(\nu(j))c(j)$ and hence
we have (5.5).
\end{proof}
\begin{quotation}
This is an example of an `extract'. The magnetization $M_0$ of the Ising
model is related to the local state probability $P(a):M_0=P(1)-P(-1)$.
The equivalences are shown in Table~\ref{eqtable}.
\end{quotation}
\begin{table}[ht]
\caption{}\label{eqtable}
\renewcommand\arraystretch{1.5}
\noindent\[
\begin{array}{|c|c|c|}
\hline
&{-\infty}&{+\infty}\\
\hline
{f_+(x,k)}&e^{\sqrt{-1}kx}+s_{12}(k)e^{-\sqrt{-1}kx}&s_{11}(k)e^
{\sqrt{-1}kx}\\
\hline
{f_-(x,k)}&s_{22}(k)e^{-\sqrt{-1}kx}&e^{-\sqrt{-1}kx}+s_{21}(k)e^{\sqrt
{-1}kx}\\
\hline
\end{array}
\]
\end{table}
\begin{definition}
This is an example of a `definition' element.
For $f\in A(X)$, we define
\begin{equation}
\mathcal{Z} (f)=\{E\in Z[X]: \text{$f$ is $E^c$-regular}\}.
\end{equation}
\end{definition}
\begin{remark}
This is an example of a `remark' element.
For $f\in A(X)$, we define
\begin{equation}
\mathcal{Z} (f)=\{E\in Z[X]: \text{$f$ is $E^c$-regular}\}.
\end{equation}
\end{remark}
\begin{example}
This is an example of an `example' element.
For $f\in A(X)$, we define
\begin{equation}
\mathcal{Z} (f)=\{E\in Z[X]: \text{$f$ is $E^c$-regular}\}.
\end{equation}
\end{example}
\begin{xca}
This is an example of the \texttt{xca} environment. This environment is
used for exercises which occur within a section.
\end{xca}
The following is an example of a numbered list.
\begin{enumerate}
\item First item.
In the case where in $G$ there is a sequence of subgroups
\[
G = G_0, G_1, G_2, \dots, G_k = e
\]
such that each is an invariant subgroup of $G_i$.
\item Second item.
Its action on an arbitrary element $X = \lambda^\alpha X_\alpha$ has the
form
\begin{equation}\label{eq:action}
[e^\alpha X_\alpha, X] = e^\alpha \lambda^\beta
[X_\alpha X_\beta] = e^\alpha c^\gamma_{\alpha \beta}
\lambda^\beta X_\gamma,
\end{equation}
\begin{enumerate}
\item First subitem.
\[
- 2\psi_2(e) = c_{\alpha \gamma}^\delta c_{\beta \delta}^\gamma
e^\alpha e^\beta.
\]
\item Second subitem.
\begin{enumerate}
\item First subsubitem.
In the case where in $G$ there is a sequence of subgroups
\[
G = G_0, G_1, G_2, \ldots, G_k = e
\]
such that each subgroup $G_{i+1}$ is an invariant subgroup of $G_i$ and
each quotient group $G_{i+1}/G_{i}$ is abelian, the group $G$ is called
\textit{solvable}.
\item Second subsubitem.
\end{enumerate}
\item Third subitem.
\end{enumerate}
\item Third item.
\end{enumerate}
Here is an example of a cite. See \cite{A}.
\begin{theorem}
This is an example of a theorem.
\end{theorem}
\begin{theorem}[Marcus Theorem]
This is an example of a theorem with a parenthetical note in the
heading.
\end{theorem}
\begin{figure}[tb]
%\blankbox{.6\columnwidth}{5pc}
\includegraphics{lion.png}
\caption{This is an example of a figure caption with text.}
\label{firstfig}
\end{figure}
\begin{figure}[tb]
%\blankbox{.75\columnwidth}{3pc}
\includegraphics{lion.png}
\caption{}\label{otherfig}
\end{figure}
\section{Some more list types}
This is an example of a bulleted list.
\begin{itemize}
\item $\mathcal{J}_g$ of dimension $3g-3$;
\item $\mathcal{E}^2_g=\{$Pryms of double covers of $C=\openbox$ with
normalization of $C$ hyperelliptic of genus $g-1\}$ of dimension $2g$;
\item $\mathcal{E}^2_{1,g-1}=\{$Pryms of double covers of
$C=\openbox^H_{P^1}$ with $H$ hyperelliptic of genus $g-2\}$ of
dimension $2g-1$;
\item $\mathcal{P}^2_{t,g-t}$ for $2\le t\le g/2=\{$Pryms of double
covers of $C=\openbox^{C'}_{C''}$ with $g(C')=t-1$ and $g(C'')=g-t-1\}$
of dimension $3g-4$.
\end{itemize}
This is an example of a `description' list.
\begin{description}
\item[Zero case] $\rho(\Phi) = \{0\}$.
\item[Rational case] $\rho(\Phi) \ne \{0\}$ and $\rho(\Phi)$ is
contained in a line through $0$ with rational slope.
\item[Irrational case] $\rho(\Phi) \ne \{0\}$ and $\rho(\Phi)$ is
contained in a line through $0$ with irrational slope.
\end{description}
\bibliographystyle{amsplain}
\begin{thebibliography}{10}
\bibitem {A} T. Aoki, \textit{Calcul exponentiel des op\'erateurs
microdifferentiels d'ordre infini.} I, Ann. Inst. Fourier (Grenoble)
\textbf{33} (1983), 227--250.
\bibitem {B} R. Brown, \textit{On a conjecture of Dirichlet},
Amer. Math. Soc., Providence, RI, 1993.
\bibitem {D} R. A. DeVore, \textit{Approximation of functions},
Proc. Sympos. Appl. Math., vol. 36,
Amer. Math. Soc., Providence, RI, 1986, pp. 34--56.
\end{thebibliography}
\end{document}
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