This graphic was converted from the following vector PostScript source code:

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sq}def/X1{9 mul exch 9 mul exch gsave translate X grestore}def/x{0 1
X1 1 1 X1 2 1 X1 1 0 X1 1 2 X1}def/X2{27 mul exch 27 mul exch gsave
translate x grestore}def/xx{0 1 X2 1 1 X2 2 1 X2 1 0 X2 1 2 X2}def
/X3{81 mul exch 81 mul exch gsave translate xx grestore}def/xxx{0 1
X3 1 1 X3 2 1 X3 1 0 X3 1 2 X3}def/X4{243 mul exch 243 mul exch gsave
translate xxx grestore}def/sqq{/s exch def 1 .7 .8 setrgbcolor 0 0
moveto s 0 rlineto 0 s rlineto s neg 0 rlineto closepath fill 0
setgray}def 240 360 translate 729 sqq 0 1 X4 1 1 X4 2 1 X4 1 0 X4 1 2
X4 0 showpage
%EOF