\documentstyle{article}
\include{tcom}
\begin{document}

\newcommand{\f3}[5]{\frac{\frac{{\textstyle #1}}{{\textstyle #2}}{#3}}{#4}{#5}}
\newcommand{\ft}[3]{\frac{#1}{#2}{{\mbox{\tiny #3}}}}
\newcommand{\fx}[4]{\frac{#1}{#2}{{\mbox{ #3 #4}}}}
%\newenvironment{Ex}{\begin{quote}\em}{\end{quote}}

\newcommand{\ova}[3]{#1\over {\displaystyle{#2 \over #3}}}
\newcommand{\ovb}[4]{#1\over {\displaystyle{#2 \over {\displaystyle {#3\over #4}}}}}
%\newcommand{\ovc}[3]{#1\over {\displaystyle{#2 \over #3}}}


% programmin in \tt: sembra non andare con \array. O meglio 
% non va con il format & e \\. Bisogna fare

\[
\begin{array}{l}
{\tt even(0)}.\\
{\tt even(ss(Y)) :- even(Y)}
\end{array}
\]

 
\begin{tt}
\begin{quote} 
member(Z,ZS) :- m1(Z,ZS) ; m2(Z,ZS).\\
m1(X,Y.XS) :- eq(X,Y).\\
m2(X,Y.YS) :- member(X,YS).\\
eq(X,X).
\end{quote} 

% tabulat come array ma in LR \[ serve a spaziare

\[
\begin{tabular} {lll}
member(Z,ZS) & :- & m1(Z,ZS) ; m2(Z,ZS).\\
m1(X,Y.XS) & :- & eq(X,Y).\\
m2(X,Y.YS) & :- & member(X,YS).\\
eq(X,X).
\end{tabular}
\]


\end{tt}

% tricks: proof-trees ?

\newcommand{\tree [4]} {{\displaystyle \frac {}{#2}{#3}}}

\[
{\textstyle \frac 
			{\frac{AAA}{BBB}}
				{CCC} }
\]

\newenvironment{refTheorem}[1]
 {\par\bigskip\noindent{\bf Theorem \ref{#1}} \it}
 {\par\bigskip}

        Questo non so: prova a togliere i \par, e se non funziona ancora,
        cambia il tutto in un \newcommand.  Cosi':

\newcommand{\refTheorem}[2]
 {\par\bigskip\noindent{\bf Theorem \ref{#1}}{\it #2}\par\bigskip}

        che chiami con

                \refTheorem{label}{cazzate}


\end{document}

