%!

% plot of {ab = 256 mod 691}

% Noam D. Elkies, 1998

0 setlinewidth

36 36 translate
.72 dup scale

/plot{
  gsave
  translate
  newpath
  0 -1.67 moveto 0 1.67 lineto
  -1.67 0 moveto 1.67 0 lineto
  stroke
  grestore
  } def

/p 691 def
/m 256 def
/g 3 def
/g1 461 def

0 0 moveto
0 p lineto p p lineto p 0 lineto closepath stroke

/a 1 def
/b m def
1 1 p 1 sub{
  pop
  /a a g mul p mod def
  /b b g1 mul p mod def
  a b plot
  } for

/center{dup stringwidth exch -2 div exch rmoveto show} def
/Times-Roman findfont p .1 mul scalefont setfont
p .5 mul p 1.2 mul moveto
(x y  =  256  mod  691) center

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