vardef C.xii(expr n) =
 save s,t,p,q;
 q=fontsize n;
 def s=infont "Times" scaled(q/fontsize"Times"/2)enddef;
 def t=shifted(xpart urcorner p,0)enddef;
 picture p; p="1"s shifted(0,q/3);
 addto p also char164 s scaled2 t;
 addto p also "2"s t;
 p enddef;