This is the anniversary of 9/11, I will be brief.
 A classical mandelbrot rendered with the Carlson stalk  plotting algorithm and
 outside=summ.Ready made at  http://maxitersfractalfollies.blogspot.com.


fract380.gif       { ; carlson mandelbrot
                     ; blank
                     ; calctime   0:02:35.28
                     ; created Sep 11, 2010
                     ;  Fractint Version 2004 Patchlevel 9
  reset=2004 type=formula formulafile=_m.frm
  formulaname=Mandel_Rings
  center-mag=-0.349298/-0.0653489/0.7966487/1/-30.0000000000036948/-3.3535\
  3828040396706e-011 params=0.08/0/2/128 float=y maxiter=1500 inside=0
  outside=summ
  colors=00A00Azbezbeyadyady`cy`bx_bxZaxZaxY`wY_wX_wXZwWZvWYvVXvUXvUWuTWuT\
  VuSUuSUtRTtRTtQStPRsPRsOQsOQsNPrNOrMOrMNrLNqKMqKLqJLqJKpIKpIJpHIpHIoGHoF\
  HoFGoEFnEFnDEnDEnCDmCCmBCmABmABl9Al99l89l88k78k77k66k56j55j45j44j33i33i2\
  2i22i11h00h00g00g00f00e00e00d00c00c00b00b00a00`00`00_00Z00Z00Y00X00X00W0\
  0W00V00U00U00T00S00S00R00Q00Q00P00P00O00N00N00M00L00L00K00J00J00I00I00H0\
  0G00G00F00E00E00D00C00C00B00A00mmzmmzllzkkyjjyiixhhxggxffweeweevddvccvbb\
  uaau``t__tZZtYYsYYsXXrWWrVVqUUqTTqSSpRRpQQoPPoPPoOOnNNnMMmLLmKKmJJlIIlHH\
  kHHkGGjFFjEEjDDiCCiBBhAAh99h99g88g77f66f55f44e33e22d11d00c00c00c00b00b00\
  a00a00a00`00`00_00_00Z00Z00Z00Y00Y00X00X00W00W00W00V00V00U00U00U00T00T00\
  S00S00R00R00R00Q00Q00P00P00O00O00O00N00N00M00M00L00L00L00K00K00J00J00J00\
  I00I00H00H00G00G00G00F00F00E00E00D00D00D00C00C00B00B00A
  }
frm:Mandel_Rings {; Copyright (c) Paul W. Carlson, 1998
  z = w = k = iter = range_num = bailout = 0
  c = pixel
  ring_width = real(p1)
  num_ranges = real(p2)
  colors_in_range = imag(p2)
  index_factor = (colors_in_range - 1) / ring_width
  :
  w = w * w + c
    ;
  dist = abs(|w|-.25)
  IF (dist < ring_width && iter > 0)
    bailout = 1
    z = index_factor * dist + range_num * colors_in_range + 1
  ENDIF
  range_num = range_num + 1
  IF (range_num == num_ranges)
    range_num = 0
  ENDIF
  iter = iter + 1
  z = z - iter
  bailout == 0 && |w| < 1.0e20
  ;SOURCE: carlson2.frm
}
Roger Alexander