[texhax] Insert numbers of figures on environment Beamer

[Darío]

Hi list, i am doing a presentation using Beamer, and the problem i
have it when i put the numbers of figures, i uses:

\documentclass{beamer}
\usepackage[spanish,activeacute]{babel} % acentos comunes
\usepackage[utf8]{inputenc} %si se usa Windows cambiar utf8 por latin1
\usepackage{fancyhdr}
\usepackage{upgreek}
\usepackage{times}
\usepackage{gensymb}
\usepackage{graphicx}
\usepackage{textcomp}
\usepackage[intlimits]{amsmath}
\usepackage{amssymb}
\usepackage{amsfonts}
\usepackage{float}
\usepackage{capt-of}
\usepackage{captdef}
\usepackage{hyperref}
\usetheme{Goettingen}

\begin{document}
\maketitle

% for example
\begin{frame}

\begin{center}
\frametitle{Campana de resonancia}
{\includegraphics[width=50mm,height=20mm]{/media/datos/Laboratorio2/ultrasonido/espectro_sonoro}}
\captionof{figure}{\small{Espectro sonoro}}
\label{espectro}
\end{center}

\end{frame}

when i compile does not appear for example "Figure n: Espectro sonoro"
This is my first use in this environment, but in
\documentclass{article} and the numbers on figures working perfectly.

Thanks all

-- 
Darío
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Por favor, no utilice formatos de archivo propietarios para el intercambio
de documentos, como ser DOC, XLS, BMP, PPT, RAR, MP3, DWG,
MOV, FLV, WMV, etc.  sino  ODT, ODS, DJVU, PDF, TXT,
CSV, PNG, FLAC, OGV, GZ o cualquier otro que no obligue a utilizar
un programa de un fabricante concreto.
Info: http://www.gnu.org/philosophy/no-word-attachments.es.html
       http://www.vaslibre.org.ve/publicaciones/odfvsooxml-es.pdf
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      ): :(
     :o_o:
       "-"