/depth 0 def
/maxdepth 10 def
/down {/depth depth 1 add def} def
/up {/depth depth 1 sub def} def

/DoLine
{ 0 350 rlineto currentpoint
  stroke translate 0 0 moveto} def

/FractArrow
{ gsave .7 .7 scale
  down DoLine
  depth maxdepth le
  { 135 rotate FractArrow
    -270 rotate FractArrow} if
  up grestore} def

/g {/depth 0 def /maxdepth exch def initgraphics 0 setlinewidth
erasepage 400 400 moveto
FractArrow stroke} def

