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\title{This is the title for my paper}
\author{First M. Last}

\begin{document}
\maketitle

\section{Introduction}

Consider the following definition.

\begin{defn}\label{happydef}
A \em{happy} number is a number that satisfies ...
\end{defn}

Clearly, 1, 7, and 10 are examples of happy numbers.  Here is some more of the introduction.  Here is some more.

Now consider the following theorem which can be found as Theorem 3.1.2 of
\cite{stillwell}.

\begin{thm}\label{happythm}
If $n$ satisfies ..., then $n$ is a happy number.
\end{thm}

The proof is too complicated to pursue here and would take us away from the
main point of the paper.

Here is some more introduction ....

\section{First Main Section}

In this section, we consider the problem of ....  The statement of this
problem and its connection with happy numbers was introduced by Grundman
and Teeple in \cite{grundman}.

We now consider the following problem ....  Here is some more of this
section.

\section{Another section}

It is a consequence of Theorem~\ref{happythm} that ....
This leads us to the following problem.  Consider ....

\section{Here is the last section}

We summarize by saying ....



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