Robert Sherry rsherry8 at comcast.net
Wed Sep 10 20:08:26 CEST 2003

     I would like to write n choose 2 using the standard mathematical symbol
of parenthesis and n written above 2 with nothing between them. From reading
the documentation, I thought the following would do it:

\begin{displaymath}
\binom{r}{2}
\end{displaymath}

However, LaTeX says that \binom is an undefined control sequence. I am using