rence is a quadratic residue mod 17. The <tt>paley</tt> function creates such a graph.
         </p><pre class="codeinput">g = graph;
paley(g,17);
</pre><h2>Maximum clique<a name="2"></a></h2>
         <p>We use <tt>omega</tt> to find the clique number and a maximum clique.
         </p><pre class="codeinput">[w,S] = omega(g);
disp([<span class="string">'The clique number is '</span>, int2str(w)])
notS = setdiff(1:17,S);
p = partition({S,notS});
clf;cdraw(g,p);
</pre><pre class="codeoutput">Optimization ter