path p;
u:=6;
x:=10;
y:=10;
dist:=4;
p:=fullcircle scaled (2*u);
picture h[];
draw p;
drawarrow (u,0)--(dist*u,0);
drawarrow (0,u)--(0,dist*u);
h1:=currentpicture;
currentpicture:=nullpicture;
dist:=dist+1;
for n=0 upto x:
   for m=0 upto y:
      draw h1 shifted (n*dist*u,m*dist*u);
   endfor;
endfor;
clip currentpicture to (-u,-u)--(x*dist*u+u,-u)--(x*dist*u+u,y*dist*u+u)--(-u,y*dist*u+u)--cycle;
label.llft(btex $0,0$ etex,(-u,-u));
label.lrt(btex $0,n$ etex,(x*dist*u,-u));
label.ulft(btex $n,0$ etex,(-u,y*dist*u));
currentpicture:=currentpicture scaled 0.75;