Fifth Homework Set Answers

8. One approach is to count the number of missing squares of size 1/4, 1/8, 1/16, and 1/32 in the lower left, lower right, and upper left corners. The red dots represent the lower right and upper left corners; the blue dots the lower left corner. These distributions are different from one another, so the entire distribution cannot be self-similar.
sizelower leftlower rightupper left
1/4211
1/8433
1/16899
1/32162727
 
Another approach is to count the missing squares for the whole shape and compare that to the one of the corners.
sizelower leftlower rightwhole shape
1/2001
1/4214
1/84310
1/168926
1/32162770
Certainly, the blue and green graphs are different, so the shape does not represent a self-similar distribution.
If we continue the pattern begun in this picture, we see the number of holes of size 1/2n is 2n-1 for the lower left corner, 3n-1 for the lower right and upper left corners, and consequently 2n-1 + 2*(3n-1) for the entire shape. In the limit, the contribution to the whole shape of the lower left corner is negligible compared with those of the lower right and upper left corners. The whole shape has a distribution similar to that of these corners, but not to that of the lower left corner.

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