%!PS-Adobe-2.0

51 .5 551
{ /x exch def
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    201 div
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    201 div
    1 index
    1 index
    31 -1 1
    { /n exch def
      1 index
      dup mul
      1 index
      dup mul
      1 index
      1 index
      add
      /d exch def
      sub
      4 index add
      3 1 roll
      2 mul mul
      2 index add
      d 4 gt
      {exit} if
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    pop pop pop pop
    n 31 div
    setgray
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    .5 0 rlineto
    0 .5 rlineto
    -.5 0 rlineto
    fill
  } for
} for
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