# Beamer: itemize in presentation mode with lemma duplicates slide

Consider this MWE:

\documentclass{beamer}
\begin{document}
\begin{frame}
\begin{itemize}[<+->]
\item Next up a lemma.
\item \begin{lemma}A lemma.\end{lemma}
\end{itemize}
\end{frame}
\end{document}


I would expect to get a pdf file with two pages, but the first page is duplicated and in fact I receive three pages.

What can I do? I noticed that

\item Something: \begin{lemma}A lemma.\end{lemma}


is split up across two slides, so <+-> might interfere with lemma.

One possibility is to omit the second \item. In your example, this seems the right option to me:

\documentclass{beamer}
\begin{document}
\begin{frame}
\begin{itemize}[<+->]
\item Next up a lemma.
\begin{lemma}A lemma.\end{lemma}
\end{itemize}
\end{frame}
\end{document}


Alternatively, if you need the \item (e.g. for the \item Something case), you can explicitly override the overlay increment for the lemma:

\documentclass{beamer}
\begin{document}
\begin{frame}
\begin{itemize}[<+->]
\item Next up a lemma.
\item Something
\begin{lemma}<.->A lemma.\end{lemma}
\end{itemize}
\end{frame}
\end{document}

• Thanks! Answer 1 is not perfect, since I want multiple theorems numbered (my itemize is in fact an enumerate, I oversimplified my MWE). So I can't (don't want to) omit the \itemize. Answer 2 is JUST what I need. Perfect! – bers Apr 22 '15 at 0:09