At Rene's suggestion, I have plotted Rayman's counts
  of  distinct characters per page:
  
    cat rayman-char-counts.txt | tr ',' ' ' > .tmp
    
    gnuplot <<EOF
    set term pbm color
    set output "rayman-char-counts.ppm"
    set xrange [0:500]
    set xlabel "total chars"
    set yrange [0:40]
    set ylabel "distinct chars"
    plot ".tmp" \
      using 2:3 title "f1r--f51v" with points
    quit
    EOF
  
    ppmtogif < rayman-char-counts.ppm > rayman-char-counts.gif
    xv rayman-char-counts.{ppm,gif}